Routing and
ICND2 200-105
Official Cert Guide
with contributing author


Cisco Press
800 East 96th Street
Indianapolis, IN 46240

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CCNA Routing and Switching ICND2 200-105 Official Cert Guide

CCNA Routing and Switching ICND2
200-105 Official Cert Guide
Wendell Odom with contributing author Scott Hogg
Copyright© 2017 Pearson Education, Inc.
Published by:
Cisco Press
800 East 96th Street
Indianapolis, IN 46240 USA
All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means,
electronic or mechanical, including photocopying, recording, or by any information storage and retrieval
system, without written permission from the publisher, except for the inclusion of brief quotations in a
Printed in the United States of America
First Printing July 2016
Library of Congress Control Number: 2016936746
ISBN-13: 978-1-58720-579-8
ISBN-10: 1-58720-579-3

Warning and Disclaimer
This book is designed to provide information about the Cisco ICND2 200-105 exam for CCNA Routing
and Switching certification. Every effort has been made to make this book as complete and as accurate as
possible, but no warranty or fitness is implied.
The information is provided on an “as is” basis. The authors, Cisco Press, and Cisco Systems, Inc. shall
have neither liability nor responsibility to any person or entity with respect to any loss or damages
arising from the information contained in this book or from the use of the discs or programs that may
accompany it.
The opinions expressed in this book belong to the author and are not necessarily those of Cisco
Systems, Inc.

Trademark Acknowledgments
All terms mentioned in this book that are known to be trademarks or service marks have been appropriately capitalized. Cisco Press or Cisco Systems, Inc., cannot attest to the accuracy of this information.
Use of a term in this book should not be regarded as affecting the validity of any trademark or service

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For questions about sales outside the U. Readers’ feedback is a natural continuation of this process. Feedback Information At Cisco Press. our goal is to create in-depth technical books of the highest quality and value. If you have any comments regarding how we could improve the quality of this book. please contact our corporate sales department at corpsales@pearsoned. Elan Beer Business Operation marketing focus.. Inc. For government sales inquiries. We greatly appreciate your assistance. and content particular to your business. Editor-in-Chief: Mark Taub Copy Editor: Bill McManus Product Line Manager: Brett Bartow Technical Editor(s): Aubrey Adams. Proofreader: Paula Lowell 9781587205798_BOOK. or branding interests).com. training goals. please contact or (800) 382-3419.S. custom cover designs. you can contact us through email at feedback@ciscopress. or for special sales opportunities (which may include electronic versions. Each book is crafted with care and precision. Cisco Press: Jan Cornelssen Editorial Assistant: Vanessa Evans Managing Editor: Sandra Schroeder Cover Designer: Chuti Prasertsith Development Editor: Drew Cupp Composition: Bronkella Publishing Senior Project Editor: Tonya Simpson Indexer: Publishing Works. please contact governmentsales@pearsoned. or otherwise alter it to better suit your needs.iii Special Sales For information about buying this title in bulk quantities. Please make sure to include the book title and ISBN in your message.indb iii 6/1/16 12:01 PM . undergoing rigorous development that involves the unique expertise of members from the professional technical

CCNP ROUTE. 5133. CCNP QoS. 1624 (Emeritus). CCNA R&S. and a member of the Infoblox IPv6 Center of Excellence (COE). and Security. (GTRI). CCIE No. CCNA DC. This book is his 27th edition of some product for He has worked as a network engineer. and CCIE R&S. founding member of the Rocky Mountain IPv6 Task Force (RMv6TF). Scott authored the Cisco Press book IPv6 Security. About the Contributing Author Scott Hogg. and certification guides throughout the years for CCENT. 4610.iv CCNA Routing and Switching ICND2 200-105 Official Cert Guide About the Author Wendell Odom. instructor. is the CTO for Global Technology Resources. and other resources at http://www. CISSP No.certskills. and he is the author of all editions of the CCNA Routing and Switching and CCENT Cert Guides from Cisco Press. Cloud. systems engineer.indb iv 6/1/16 12:01 PM . he currently works writing and creating certification study tools. consultant. links to his blogs. has been in the networking industry since 1981. He maintains study tools. SDN. Scott is a frequent presenter and writer on topics including IPv6. CCIE No. and course developer. Inc. Scott is a Cisco Champion. 9781587205798_BOOK. He helped develop the popular Pearson Network Simulator. He has written books about topics from networking basics.

performing data center and network audits. and the Middle East. Africa. and troubleshooting as well as service provider technologies. Aubrey has technically reviewed a number of Pearson Education and Cisco Press publications. Elan Beer. 9781587205798_BOOK.indb v 6/1/16 12:01 PM . With a background in telecommunications design. and assisting clients with their short. 1837. and online products. and in 1996.and long-term design objectives. is a senior consultant and Cisco instructor specializing in data center architecture and multiprotocol network design. In 1993. graduate diplomas in computing and education. Most recently. Australia. and switching. Elan was among the first to obtain the Cisco Certified System Instructor (CCSI) certification.v About the Technical Reviewers Aubrey Adams is a Cisco Networking Academy instructor in Perth. configuration. routing. Elan has been focused on data center design. Elan has used his expertise to design and troubleshoot data centers and internetworks in Malaysia. Elan has been involved in numerous large-scale data center and telecommunications networking projects worldwide. the Cisco Certified Internetworking Expert. China. Western Australia. Elan has been instrumental in large-scale professional service efforts designing and troubleshooting internetworks. simulation. Since then. and associated industry certifications. Europe. he was among the first to attain Cisco System’s highest technical certification. Since 2007. For the past 27 years. CCIE No. Aubrey has qualifications in electronic engineering and management. including video. Elan has designed networks and trained thousands of industry experts in data center architecture. North America. Elan has a global perspective of network architectures via his international clientele. He has taught across a broad range of both related vocational and education training areas and university courses.

vi CCNA Routing and Switching ICND2 200-105 Official Cert Guide Dedications For Kris Odom. doll. Love you. 9781587205798_BOOK. my wonderful wife: The best part of everything we do together in life.indb vi 6/1/16 12:01 PM .

it is done well and beautifully. Many thanks to Aubrey and Elan. In particular. 9781587205798_BOOK. Lisa! I love the magic wand that is production. Thanks for managing the whole production process again. We’ve worked together on probably 20+ titles now. Hank Preston of Cisco Systems. Hank helped me refine my understanding based on his great experience with helping Cisco customers implement cloud computing. they do it all. IT as a Service Architect. And Tonya. Thanks to Sandra Schroeder. it’s a much better book because of the two of you. the juggling act continues. he was the driving force behind adding all the new apps to the DVD/web. That work included many new math-related apps in the ICND1 book. and all the production team for making the magic happen. for the timely input.indb vii 6/1/16 12:01 PM . As always. but his insights definitely made the chapter much better and more realistic. and an important part of deciding what the entire Official Cert Guide series direction should be. just as they did for the ICND1 100-105 Cert Guide. Presto. He took over the job for this book during a pretty high-stress and high-load timeframe. Tonya Simpson. Drew Cupp did his usual wonderful job with this book as development editor. for finding those small technical areas. Besides the usual wisdom and good decision making to guide the project.vii Acknowledgments Brett Bartow again served as associate publisher and executive editor on the book. for taking the time to read and think about every new part of the book. Joe Stralo. Thanks for the hard work. Brett has been a pleasure to work with. thanks for putting it all together and making it look easy. and Phil Vancil were a great help while we worked on these titles. and once again. we work in concert with Cisco. but also many new features that sit on the DVD and on this book’s website as review tools. from the breadth of some of the new topics. A special thanks goes out to various people on the Cisco team who work with Pearson to create Cisco Press books. This book presented a little more of a challenge. and delivered with excellence. Thanks Drew for jumping in and getting into the minutia while keeping the big-picture features on track. gave me some valuable assistance when researching before writing the cloud computing chapter (27). And thanks for the work on the online/DVD elements as well! Aubrey Adams and Elan Beer both did a great job as technical editors for this book. Greg Cote. just keeping focus with such a long pair of books in a short time frame. As part of writing these books. Truly. and for telling me where I need to do more. From fixing all my grammar. and out pops these beautiful books. Welcome and thanks to Lisa Matthews for her work on the DVD and online tools. like the Key Topics reviews. crummy word choices. and co-author of the Cisco Press CCNA Cloud CLDADM 210-455 Cert Guide. once again getting the “opportunity” to manage two books with many elements at the same timeline. and passive-voice sentences to pulling the design and layout together. Hank did not write the chapter. Word docs with gobs of queries and comments feed into the machine. Once again.

viii CCNA Routing and Switching ICND2 200-105 Official Cert Guide The figures in the book continue to be an important part of the book. Lord of everything in my life. Thanks for the usual fine work. And thanks to Jesus Christ. No way the books are out on time without Sean’s efforts. Kris. owns big parts of the lab development process for the associated labs added to my blogs. Chris owns the mind map process now.indb viii 6/1/16 12:01 PM . with a great deal of attention paid to choosing how to use figures to communicate ideas. by design. Thanks to my daughter Hannah. A longtime co-collaborator with Pearson’s CCNA Simulator. Sean! A special thanks to you readers who submit suggestions and point out possible errors. and then catches anything I need to toss over my shoulder so I can focus on the books. I love walking this journey with you. Thanks to my wonderful wife. 9781587205798_BOOK. Mike Tanamachi. Sean did a lot of technology work behind the scenes. and especially to those of you who post online at the Cisco Learning Network. past comments I have received directly and “overheard” by participating at CLN have made this edition a better book. Mike! I could not have made the timeline for this book without Chris Burns of Certskills Professional. Without question. who helps make this sometimes challenging work lifestyle a breeze. Chris. thanks for the great job. illustrator and mind reader. did his usual great job creating the finished figure files once again. does various tasks related to specific chapters. you are the man! Sean Wilkins played the largest role he’s played so far with one of my books. doll.

indb ix 68 437 438 460 488 516 6/1/16 12:01 PM .ix Contents at a Glance Introduction xxxv Your Study Plan 2 Part I Ethernet LANs Chapter 1 Implementing Ethernet Virtual LANs Chapter 2 Spanning Tree Protocol Concepts Chapter 3 Spanning Tree Protocol Implementation Chapter 4 LAN Troubleshooting Chapter 5 VLAN Trunking Protocol Chapter 6 Miscellaneous LAN Topics Part I Review 13 14 42 98 120 142 164 Part II IPv4 Routing Protocols Chapter 7 Understanding OSPF Concepts Chapter 8 Implementing OSPF for IPv4 Chapter 9 Understanding EIGRP Concepts Chapter 10 Implementing EIGRP for IPv4 Chapter 11 Troubleshooting IPv4 Routing Protocols Chapter 12 Implementing External BGP Part II Review 169 169 194 224 244 272 300 324 Part III Wide-Area Networks Chapter 13 Implementing Point-to-Point WANs Chapter 14 Private WANs with Ethernet and MPLS Chapter 15 Private WANs with Internet VPN Part III Review 327 328 362 386 434 Part IV IPv4 Services: ACLs and QoS Chapter 16 Basic IPv4 Access Control Lists Chapter 17 Advanced IPv4 Access Control Lists Chapter 18 Quality of Service (QoS) Part IV Review 9781587205798_BOOK.

indb x 6/1/16 12:01 PM .x CCNA Routing and Switching ICND2 200-105 Official Cert Guide Part V IPv4 Routing and Troubleshooting Chapter 19 IPv4 Routing in the LAN Chapter 20 Implementing HSRP for First-Hop Routing Chapter 21 Troubleshooting IPv4 Routing Part V Review 519 520 544 566 588 Part VI IPv6 Chapter 22 IPv6 Routing Operation and Troubleshooting Chapter 23 Implementing OSPF for IPv6 616 Chapter 24 Implementing EIGRP for IPv6 644 Chapter 25 IPv6 Access Control Lists Part VI Review 591 664 688 Part VII Miscellaneous Chapter 26 Network Management Chapter 27 Cloud Computing Chapter 28 SDN and Network Programmability Part VII Review 592 691 692 730 760 780 Part VIII Final Prep 783 Chapter 29 Final Review Part IX Appendixes Appendix A Numeric Reference Tables Appendix B Technical Content 784 801 803 810 Glossary 813 Index 852 DVD Appendixes Appendix C Answers to the “Do I Know This Already?” Quizzes Appendix D Practice for Chapter 16: Basic IPv4 Access Control Lists Appendix E Mind Map Solutions Appendix F Study Planner Appendix G Learning IPv4 Routes with RIPv2 Appendix H Understanding Frame Relay Concepts Appendix I Implementing Frame Relay Appendix J IPv4 Troubleshooting Tools Appendix K Topics from Previous Editions Appendix L Exam Topic Cross Reference 9781587205798_BOOK.

xi Contents Introduction xxxv Your Study Plan 2 A Brief Perspective on Cisco Certification Exams Five Study Plan Steps 2 3 Step 1: Think in Terms of Parts and Chapters 3 Step 2: Build Your Study Habits Around the Chapter Step 3: Use Book Parts for Major Milestones 4 5 Step 4: Use the Final Review Chapter to Refine Skills and Uncover Weaknesses 6 Step 5: Set Goals and Track Your Progress 7 Things to Do Before Starting the First Chapter 8 Find Review Activities on the Web and DVD 8 Should I Plan to Use the Two-Exam Path or One-Exam Path? 8 Study Options for Those Taking the 200-125 CCNA Exam 9 Other Small Tasks Before Getting Started 10 Getting Started: Now 11 Part I Ethernet LANs 13 Chapter 1 Implementing Ethernet Virtual LANs 14 “Do I Know This Already?” Quiz 14 Foundation Topics 16 Virtual LAN Concepts 16 Creating Multiswitch VLANs Using Trunking 18 VLAN Tagging Concepts 18 The 802.indb xi 6/1/16 12:01 PM .1Q and ISL VLAN Trunking Protocols 20 Forwarding Data Between VLANs 21 Routing Packets Between VLANs with a Router 21 Routing Packets with a Layer 3 Switch 23 VLAN and VLAN Trunking Configuration and Verification 24 Creating VLANs and Assigning Access VLANs to an Interface 24 VLAN Configuration Example 1: Full VLAN Configuration 25 VLAN Configuration Example 2: Shorter VLAN Configuration 28 VLAN Trunking Protocol 29 VLAN Trunking Configuration 30 9781587205798_BOOK.

1D) 44 The Need for Spanning Tree 45 What IEEE 802.1D Spanning Tree Does 47 How Spanning Tree Works 48 The STP Bridge ID and Hello BPDU 49 Electing the Root Switch 50 Choosing Each Switch’s Root Port 52 Choosing the Designated Port on Each LAN Segment 54 Influencing and Changing the STP Topology 54 Making Configuration Changes to Influence the STP Topology 55 Reacting to State Changes That Affect the STP Topology 55 How Switches React to Changes with STP 56 Changing Interface States with STP 57 Rapid STP (IEEE 802.xii CCNA Routing and Switching ICND2 200-105 Official Cert Guide Implementing Interfaces Connected to Phones 34 Data and Voice VLAN Concepts 34 Data and Voice VLAN Configuration and Verification Summary: IP Telephony Ports on Switches 36 38 Chapter Review 39 Chapter 2 Spanning Tree Protocol Concepts 42 “Do I Know This Already?” Quiz 43 Foundation Topics 44 Spanning Tree Protocol (IEEE 802.indb xii 6/1/16 12:01 PM .1w) Concepts 58 Comparing STP and RSTP 59 RSTP and the Alternate (Root) Port Role 60 RSTP States and Processes 62 RSTP and the Backup (Designated) Port Role 62 RSTP Port Types 63 Optional STP Features 64 EtherChannel 64 PortFast 65 Chapter 3 BPDU Guard 65 Chapter Review 66 Spanning Tree Protocol Implementation “Do I Know This Already?” Quiz 68 69 Foundation Topics 71 Implementing STP 71 9781587205798_BOOK.

xiii Setting the STP Mode 72 Connecting STP Concepts to STP Configuration Options 72 Per-VLAN Configuration Settings 72 The Bridge ID and System ID Extension 73 Per-VLAN Port Costs 74 STP Configuration Option Summary 74 Verifying STP Operation 75 Configuring STP Port Costs 78 Configuring Priority to Influence the Root Election 80 Implementing Optional STP Features 81 Configuring PortFast and BPDU Guard 81 Configuring EtherChannel 84 Configuring a Manual EtherChannel 84 Configuring Dynamic EtherChannels 86 Implementing RSTP 88 Identifying the STP Mode on a Catalyst Switch 88 RSTP Port Roles 91 RSTP Port States 92 RSTP Port Types 92 Chapter Review 94 Chapter 4 LAN Troubleshooting 98 “Do I Know This Already?” Quiz 99 Foundation Topics 99 Troubleshooting STP 99 Determining the Root Switch 99 Determining the Root Port on Nonroot Switches 101 STP Tiebreakers When Choosing the Root Port 102 Suggestions for Attacking Root Port Problems on the Exam Determining the Designated Port on Each LAN Segment 103 104 Suggestions for Attacking Designated Port Problems on the Exam STP Convergence 105 Troubleshooting Layer 2 EtherChannel 106 Incorrect Options on the channel-group Command 106 Configuration Checks Before Adding Interfaces to EtherChannels 9781587205798_BOOK.indb xiii 105 108 6/1/16 12:01 PM .

xiv CCNA Routing and Switching ICND2 200-105 Official Cert Guide Analyzing the Switch Data Plane Forwarding 109 Predicting STP Impact on MAC Tables 110 Predicting EtherChannel Impact on MAC Tables 111 Choosing the VLAN of Incoming Frames 112 Troubleshooting VLANs and VLAN Trunks 113 Access VLAN Configuration Incorrect 113 Access VLANs Undefined or Disabled 114 Mismatched Trunking Operational States 116 Mismatched Supported VLAN List on Trunks 117 Mismatched Native VLAN on a Trunk 118 Chapter Review 119 Chapter 5 VLAN Trunking Protocol 120 “Do I Know This Already?” Quiz 120 Foundation Topics 122 VLAN Trunking Protocol (VTP) Concepts 122 Basic VTP Operation 122 Synchronizing the VTP Database 124 Requirements for VTP to Work Between Two Switches VTP Version 1 Versus Version 2 VTP Pruning 126 127 127 Summary of VTP Features 128 VTP Configuration and Verification 129 Using VTP: Configuring Servers and Clients 129 Verifying Switches Synchronized Databases 131 Storing the VTP and Related Configuration 134 Avoiding Using VTP 135 VTP Troubleshooting 135 Determining Why VTP Is Not Synchronizing 136 Common Rejections When Configuring VTP 137 Problems When Adding Switches to a Network Chapter Review Chapter 6 137 139 Miscellaneous LAN Topics 142 “Do I Know This Already?” Quiz 143 Foundation Topics 144 Securing Access with IEEE 802.1x 144 9781587205798_BOOK.indb xiv 6/1/16 12:01 PM .

xv AAA Authentication 147 AAA Login Process 147 TACACS+ and RADIUS Protocols AAA Configuration Examples DHCP Snooping 147 148 150 DHCP Snooping Basics 151 An Example DHCP-based Attack How DHCP Snooping Works 152 152 Summarizing DHCP Snooping Features 154 Switch Stacking and Chassis Aggregation 155 Traditional Access Switching Without Stacking 155 Switch Stacking of Access Layer Switches 156 Switch Stack Operation as a Single Logical Switch 157 Cisco FlexStack and FlexStack-Plus 158 Chassis Aggregation 159 High Availability with a Distribution/Core Switch 159 Improving Design and Availability with Chassis Aggregation Chapter Review Part I Review 160 162 164 Part II IPv4 Routing Protocols 169 Chapter 7 Understanding OSPF Concepts “Do I Know This Already?” Quiz 170 170 Foundation Topics 172 Comparing Dynamic Routing Protocol Features 172 Routing Protocol Functions 172 Interior and Exterior Routing Protocols 173 Comparing IGPs 175 IGP Routing Protocol Algorithms 175 Metrics 175 Other IGP Comparisons 176 Administrative Distance 177 OSPF Concepts and Operation 178 OSPF Overview 179 Topology Information and LSAs 179 Applying Dijkstra SPF Math to Find the Best Routes 9781587205798_BOOK.indb xv 180 6/1/16 12:01 PM .

indb xvi 6/1/16 12:01 PM .xvi CCNA Routing and Switching ICND2 200-105 Official Cert Guide Becoming OSPF Neighbors 180 The Basics of OSPF Neighbors 181 Meeting Neighbors and Learning Their Router ID 181 Exchanging the LSDB Between Neighbors 183 Fully Exchanging LSAs with Neighbors 183 Maintaining Neighbors and the LSDB 184 Using Designated Routers on Ethernet Links 185 Calculating the Best Routes with SPF 186 OSPF Area Design 188 OSPF Areas 189 How Areas Reduce SPF Calculation Time 190 OSPF Area Design Advantages 191 Chapter Review 191 Chapter 8 Implementing OSPF for IPv4 194 “Do I Know This Already?” Quiz 194 Foundation Topics 196 Implementing Single-Area OSPFv2 196 OSPF Single-Area Configuration 197 Matching with the OSPF network Command 198 Verifying OSPFv2 Single Area 200 Configuring the OSPF Router ID 203 OSPF Passive Interfaces 204 Implementing Multiarea OSPFv2 206 Single-Area Configurations 207 Multiarea Configuration 209 Verifying the Multiarea Configuration 210 Verifying the Correct Areas on Each Interface on an ABR 210 Verifying Which Router Is DR and BDR 211 Verifying Interarea OSPF Routes 212 Additional OSPF Features 213 OSPF Default Routes 213 OSPF Metrics (Cost) 215 Setting the Cost Based on Interface Bandwidth 216 The Need for a Higher Reference Bandwidth 217 OSPF Load Balancing 217 9781587205798_BOOK.

xvii OSPFv2 Interface Configuration 218 OSPFv2 Interface Configuration Example 218 Verifying OSPFv2 Interface Configuration 219 Chapter Review 221 Chapter 9 Understanding EIGRP Concepts 224 “Do I Know This Already?” Quiz 224 Foundation Topics 226 EIGRP and Distance Vector Routing Protocols 226 Introduction to EIGRP 226 Basic Distance Vector Routing Protocol Features 227 The Concept of a Distance and a Vector 228 Full Update Messages and Split Horizon 229 Route Poisoning 231 EIGRP as an Advanced DV Protocol 232 EIGRP Sends Partial Update Messages.indb xvii 6/1/16 12:01 PM . As Needed 232 EIGRP Maintains Neighbor Status Using Hello 233 Summary of Interior Routing Protocol Features 233 EIGRP Concepts and Operation 234 EIGRP Neighbors 234 Exchanging EIGRP Topology Information 235 Calculating the Best Routes for the Routing Table 236 The EIGRP Metric Calculation 236 An Example of Calculated EIGRP Metrics 237 Caveats with Bandwidth on Serial Links 238 EIGRP Convergence 239 Feasible Distance and Reported Distance 240 EIGRP Successors and Feasible Successors 241 The Query and Reply Process 242 Chapter Review 243 Chapter 10 Implementing EIGRP for IPv4 244 “Do I Know This Already?” Quiz 244 Foundation Topics 246 Core EIGRP Configuration and Verification 246 EIGRP Configuration 246 Configuring EIGRP Using a Wildcard Mask 248 9781587205798_BOOK.


CCNA Routing and Switching ICND2 200-105 Official Cert Guide
Verifying EIGRP Core Features 249
Finding the Interfaces on Which EIGRP Is Enabled 250
Displaying EIGRP Neighbor Status 253
Displaying the IPv4 Routing Table 253
EIGRP Metrics, Successors, and Feasible Successors 255
Viewing the EIGRP Topology Table 255
Finding Successor Routes 257
Finding Feasible Successor Routes 258
Convergence Using the Feasible Successor Route 260
Examining the Metric Components 262
Other EIGRP Configuration Settings 262
Load Balancing Across Multiple EIGRP Routes 263
Tuning the EIGRP Metric Calculation 265
Autosummarization and Discontiguous Classful Networks 266
Automatic Summarization at the Boundary of a Classful Network 266
Discontiguous Classful Networks 267
Chapter Review 269
Chapter 11

Troubleshooting IPv4 Routing Protocols 272
“Do I Know This Already?” Quiz 272
Foundation Topics 273
Perspectives on Troubleshooting Routing Protocol Problems 273
Interfaces Enabled with a Routing Protocol 274
EIGRP Interface Troubleshooting 275
Examining Working EIGRP Interfaces 276
Examining the Problems with EIGRP Interfaces 278
OSPF Interface Troubleshooting 281
Neighbor Relationships 284
EIGRP Neighbor Verification Checks 285
EIGRP Neighbor Troubleshooting Example 286
OSPF Neighbor Troubleshooting 288
Finding Area Mismatches 290
Finding Duplicate OSPF Router IDs 291
Finding OSPF Hello and Dead Timer Mismatches 293
Other OSPF Issues 294
Shutting Down the OSPF Process 294
Mismatched MTU Settings 296
Chapter Review 296

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Chapter 12

Implementing External BGP 300
“Do I Know This Already?” Quiz


Foundation Topics 302
BGP Concepts 302
Advertising Routes with BGP
Internal and External BGP



Choosing the Best Routes with BGP
eBGP and the Internet Edge



Internet Edge Designs and Terminology


Advertising the Enterprise Public Prefix into the Internet
Learning Default Routes from the ISP
eBGP Configuration and Verification
BGP Configuration Concepts




Configuring eBGP Neighbors Using Link Addresses
Verifying eBGP Neighbors



Administratively Disabling Neighbors


Injecting BGP Table Entries with the network Command
Injecting Routes for a Classful Network
Advertising Subnets to the ISP


Learning a Default Route from the ISP

Part II Review



Advertising a Single Prefix with a Static Discard Route
Chapter Review






Part III

Wide-Area Networks


Chapter 13

Implementing Point-to-Point WANs 328
“Do I Know This Already?” Quiz


Foundation Topics 330
Leased-Line WANs with HDLC 330
Layer 1 Leased Lines


The Physical Components of a Leased Line
The Role of the CSU/DSU



Building a WAN Link in a Lab


Layer 2 Leased Lines with HDLC


Configuring HDLC 337

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CCNA Routing and Switching ICND2 200-105 Official Cert Guide
Leased-Line WANs with PPP 340
PPP Concepts 340
PPP Framing 341
PPP Control Protocols 341
PPP Authentication 342
Implementing PPP 343
Implementing PPP CHAP 344
Implementing PPP PAP 346
Implementing Multilink PPP


Multilink PPP Concepts 348
Configuring MLPPP 349
Verifying MLPPP 351
Troubleshooting Serial Links 353
Troubleshooting Layer 1 Problems 354
Troubleshooting Layer 2 Problems 354
Keepalive Failure 355
PAP and CHAP Authentication Failure 356
Troubleshooting Layer 3 Problems 357
Chapter Review 358
Chapter 14

Private WANs with Ethernet and MPLS 362
“Do I Know This Already?” Quiz 363
Foundation Topics 364
Metro Ethernet 364
Metro Ethernet Physical Design and Topology 365
Ethernet WAN Services and Topologies 366
Ethernet Line Service (Point-to-Point) 367
Ethernet LAN Service (Full Mesh) 368
Ethernet Tree Service (Hub and Spoke) 369
Layer 3 Design Using Metro Ethernet 370
Layer 3 Design with E-Line Service 370
Layer 3 Design with E-LAN Service 371
Layer 3 Design with E-Tree Service 372
Ethernet Virtual Circuit Bandwidth Profiles 373
Charging for the Data (Bandwidth) Used 373
Controlling Overages with Policing and Shaping 374

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4G. LTE) 392 Fiber Internet Access 393 Internet VPN Fundamentals 393 Site-to-Site VPNs with IPsec 395 Client VPNs with SSL 396 GRE Tunnels and DMVPN 397 GRE Tunnel Concepts 398 Routing over GRE Tunnels 398 GRE Tunnels over the Unsecured Network 400 Configuring GRE Tunnels 402 Verifying a GRE Tunnel 404 Troubleshooting GRE Tunnels 406 Tunnel Interfaces and Interface State 406 Layer 3 Issues for Tunnel Interfaces 409 Issues with ACLs and Security 409 Multipoint Internet VPNs Using DMVPN 410 PPP over Ethernet 413 PPPoE Concepts 414 PPPoE Configuration 415 PPPoE Configuration Breakdown: Dialers and Layer 1 416 PPPoE Configuration Breakdown: PPP and Layer 2 417 PPPoE Configuration Breakdown: Layer 3 417 9781587205798_BOOK.indb xxi 6/1/16 12:01 PM .xxi Multiprotocol Label Switching (MPLS) 375 MPLS VPN Physical Design and Topology 377 MPLS and Quality of Service 378 Layer 3 with MPLS VPN 379 OSPF Area Design with MPLS VPN 381 Routing Protocol Challenges with EIGRP 382 Chapter Review 383 Chapter 15 Private WANs with Internet VPN 386 “Do I Know This Already?” Quiz 386 Foundation Topics 389 Internet Access and Internet VPN Fundamentals 389 Internet Access 389 Digital Subscriber Line 390 Cable Internet 391 Wireless WAN (3G.

xxii CCNA Routing and Switching ICND2 200-105 Official Cert Guide PPPoE Configuration Summary 418 A Brief Aside About Lab Experimentation with PPPoE PPPoE Verification 419 420 Verifying Dialer and Virtual-Access Interface Bindings Verifying Virtual-Access Interface Configuration Verifying PPPoE Session Status 425 425 Step 0: Status Before Beginning the First Step Step 1: Status After Layer 1 Configuration 426 427 Step 2: Status After Layer 2 (PPP) Configuration Step 3: Status After Layer 3 (IP) Configuration PPPoE Troubleshooting Summary Chapter Review Part III Review 422 424 Verifying Dialer Interface Layer 3 Status PPPoE Troubleshooting 421 428 429 430 430 434 Part IV IPv4 Services: ACLs and QoS Chapter 16 Basic IPv4 Access Control Lists “Do I Know This Already?” Quiz 437 438 438 Foundation Topics 440 IPv4 Access Control List Basics 440 ACL Location and Direction 440 Matching Packets 441 Taking Action When a Match Occurs 442 Types of IP ACLs 442 Standard Numbered IPv4 ACLs 443 List Logic with IP ACLs 444 Matching Logic and Command Syntax 445 Matching the Exact IP Address 445 Matching a Subset of the Address with Wildcards Binary Wildcard Masks 446 447 Finding the Right Wildcard Mask to Match a Subnet Matching Any/All Addresses 448 Implementing Standard IP ACLs 448 Standard Numbered ACL Example 1 449 Standard Numbered ACL Example 2 450 448 Troubleshooting and Verification Tips 452 9781587205798_BOOK.indb xxii 6/1/16 12:01 PM .

and Destination IP 463 Matching TCP and UDP Port Numbers 464 Extended IP ACL Configuration 467 Extended IP Access Lists: Example 1 468 Extended IP Access Lists: Example 2 469 Practice Building access-list Commands 470 Named ACLs and ACL Editing 471 Named IP Access Lists 471 Editing ACLs Using Sequence Numbers 473 Numbered ACL Configuration Versus Named ACL Configuration 475 ACL Implementation Considerations 476 Troubleshooting with IPv4 ACLs 477 Analyzing ACL Behavior in a Network 477 ACL Troubleshooting Commands 479 Example Issue: Reversed Source/Destination IP Addresses 480 Steps 3D and 3E: Common Syntax Mistakes 481 Example Issue: Inbound ACL Filters Routing Protocol Packets 481 ACL Interactions with Router-Generated Packets 483 Local ACLs and a Ping from a Router 483 Router Self-Ping of a Serial Interface IPv4 Address 483 Router Self-Ping of an Ethernet Interface IPv4 Address 484 Chapter Review 485 Chapter 18 Quality of Service (QoS) 488 “Do I Know This Already?” Quiz 488 Foundation Topics 490 Introduction to QoS 490 QoS: Managing Bandwidth. and Loss 491 Types of Traffic 492 Data Applications 492 Voice and Video Applications 493 9781587205798_BOOK. Delay. Jitter.indb xxiii 6/1/16 12:01 PM .xxiii Practice Applying Standard IP ACLs 453 Practice Building access-list Commands 454 Reverse Engineering from ACL to Address Range 454 Chapter Review 456 Chapter 17 Advanced IPv4 Access Control Lists 460 “Do I Know This Already?” Quiz 461 Foundation Topics 462 Extended Numbered IP Access Control Lists 462 Matching the Protocol. Source IP.

and Video 507 Shaping and Policing 507 Policing 508 Where to Use Policing Shaping 509 510 Setting a Good Shaping Time Interval for Voice and Video 511 Congestion Avoidance 512 TCP Windowing Basics 512 Congestion Avoidance Tools 513 Chapter Review 514 Part IV Review 516 Part V IPv4 Routing and Troubleshooting Chapter 19 IPv4 Routing in the LAN 519 520 “Do I Know This Already?” Quiz 521 Foundation Topics 522 VLAN Routing with Router 802.xxiv CCNA Routing and Switching ICND2 200-105 Official Cert Guide QoS as Mentioned in This Book 495 QoS on Switches and Routers 495 Classification and Marking 495 Classification Basics 495 Matching (Classification) Basics 496 Classification on Routers with ACLs and NBAR 497 Marking IP DSCP and Ethernet CoS 499 Marking the IP Header 499 Marking the Ethernet 802.indb xxiv 6/1/16 12:01 PM .1Q Header Other Marking Fields 500 501 Defining Trust Boundaries 501 DiffServ Suggested Marking Values 502 Expedited Forwarding (EF) 502 Assured Forwarding (AF) 502 Class Selector (CS) 503 Congestion Management (Queuing) 504 Round Robin Scheduling (Prioritization) 505 Low Latency Queuing 505 A Prioritization Strategy for Data. Voice.1Q Trunks 522 Configuring ROAS 524 Verifying ROAS 526 Troubleshooting ROAS 528 9781587205798_BOOK.

indb xxv 572 6/1/16 12:01 PM .xxv VLAN Routing with Layer 3 Switch SVIs 529 Configuring Routing Using Switch SVIs 529 Verifying Routing with SVIs 531 Troubleshooting Routing with SVIs 532 VLAN Routing with Layer 3 Switch Routed Ports 534 Implementing Routed Interfaces on Switches 535 Implementing Layer 3 EtherChannels 537 Troubleshooting Layer 3 EtherChannels 541 Chapter Review 541 Chapter 20 Implementing HSRP for First-Hop Routing 544 “Do I Know This Already?” Quiz 544 Foundation Topics 546 FHRP and HSRP Concepts 546 The Need for Redundancy in Networks 547 The Need for a First Hop Redundancy Protocol 549 The Three Solutions for First-Hop Redundancy 550 HSRP Concepts 551 HSRP Failover 552 HSRP Load Balancing 553 Implementing HSRP 554 Configuring and Verifying Basic HSRP 554 HSRP Active Role with Priority and Preemption 556 HSRP Versions 559 Troubleshooting HSRP 560 Checking HSRP Configuration 560 Symptoms of HSRP Misconfiguration 561 Chapter Review 563 Chapter 21 Troubleshooting IPv4 Routing 566 “Do I Know This Already?” Quiz 567 Foundation Topics 567 Problems Between the Host and the Default Router 567 Root Causes Based on a Host’s IPv4 Settings 568 Ensure IPv4 Settings Correctly Match 568 Mismatched Masks Impact Route to Reach Subnet 569 Typical Root Causes of DNS Problems 571 Wrong Default Router IP Address Setting 9781587205798_BOOK.

indb xxvi 6/1/16 12:01 PM .xxvi CCNA Routing and Switching ICND2 200-105 Official Cert Guide Root Causes Based on the Default Router’s Configuration 572 DHCP Issues 573 Router LAN Interface and LAN Issues 575 Problems with Routing Packets Between Routers 576 IP Forwarding by Matching the Most Specific Route 577 Using show ip route and Subnet Math to Find the Best Route 577 Using show ip route address to Find the Best Route 579 show ip route Reference 579 Routing Problems Caused by Incorrect Addressing Plans 581 Recognizing When VLSM Is Used or Not 581 Overlaps When Not Using VLSM 581 Overlaps When Using VLSM 583 Configuring Overlapping VLSM Subnets 584 Pointers to Related Troubleshooting Topics 585 Router WAN Interface Status 585 Filtering Packets with Access Lists 586 Chapter Review 586 Part V Review 588 Part VI IPv6 591 Chapter 22 IPv6 Routing Operation and Troubleshooting 592 “Do I Know This Already?” Quiz 592 Foundation Topics 592 Normal IPv6 Operation 592 Unicast IPv6 Addresses and IPv6 Subnetting 593 Assigning Addresses to Hosts 595 Stateful DHCPv6 596 Stateless Address Autoconfiguration 597 Router Address and Static Route Configuration 598 Configuring IPv6 Routing and Addresses on Routers 598 IPv6 Static Routes on Routers 599 Verifying IPv6 Connectivity 600 Verifying Connectivity from IPv6 Hosts 600 Verifying IPv6 from Routers 601 Troubleshooting IPv6 604 Pings from the Host Work Only in Some Cases 605 Pings Fail from a Host to Its Default Router 606 9781587205798_BOOK.

But Fails 610 Routing Looks Good.xxvii Problems Using Any Function That Requires DNS 607 Host Is Missing IPv6 Settings: Stateful DHCP Issues 608 Host Is Missing IPv6 Settings: SLAAC Issues 609 Traceroute Shows Some Hops. But Traceroute Still Fails 612 Chapter Review 612 Chapter 23 Implementing OSPF for IPv6 616 “Do I Know This Already?” Quiz 616 Foundation Topics 618 OSPFv3 for IPv6 Concepts 618 IPv6 Routing Protocol Versions and Protocols 619 Two Options for Implementing Dual Stack with OSPF 619 OSPFv2 and OSPFv3 Internals 621 OSPFv3 Configuration 621 Basic OSPFv3 Configuration 621 Single-Area Configuration on the Three Internal Routers 623 Adding Multiarea Configuration on the Area Border Router 625 Other OSPFv3 Configuration Settings 626 Setting OSPFv3 Interface Cost to Influence Route Selection 626 OSPF Load Balancing 627 Injecting Default Routes 627 OSPFv3 Verification and Troubleshooting 628 OSPFv3 Interfaces 630 Verifying OSPFv3 Interfaces 630 Troubleshooting OSPFv3 Interfaces 631 OSPFv3 Neighbors 632 Verifying OSPFv3 Neighbors 632 Troubleshooting OSPFv3 Neighbors 633 OSPFv3 LSDB and LSAs 636 The Issue of IPv6 MTU 636 OSPFv3 Metrics and IPv6 Routes 638 Verifying OSPFv3 Interface Cost and Metrics 638 Troubleshooting IPv6 Routes Added by OSPFv3 640 Chapter Review 642 9781587205798_BOOK.indb xxvii 6/1/16 12:01 PM .

xxviii CCNA Routing and Switching ICND2 200-105 Official Cert Guide Chapter 24 Implementing EIGRP for IPv6 644 “Do I Know This Already?” Quiz 644 Foundation Topics 646 EIGRP for IPv6 Configuration 646 EIGRP for IPv6 Configuration Basics 647 EIGRP for IPv6 Configuration Example 648 Other EIGRP for IPv6 Configuration Settings 650 Setting Bandwidth and Delay to Influence EIGRP for IPv6 Route Selection 650 EIGRP Load Balancing EIGRP Timers 651 652 EIGRP for IPv6 Verification and Troubleshooting EIGRP for IPv6 Interfaces 654 EIGRP for IPv6 Neighbors 656 EIGRP for IPv6 Topology Database EIGRP for IPv6 Routes Chapter Review Chapter 25 653 657 659 661 IPv6 Access Control Lists 664 “Do I Know This Already?” Quiz 664 Foundation Topics 666 IPv6 Access Control List Basics 666 Similarities and Differences Between IPv4 and IPv6 ACLs 666 ACL Location and Direction 667 IPv6 Filtering Policies 668 ICMPv6 Filtering Caution 668 Capabilities of IPv6 ACLs 669 Limitations of IPv6 ACLs 669 Matching Tunneled Traffic 670 IPv4 Wildcard Mask and IPv6 Prefix Length ACL Logging Impact Router Originated Packets 670 Configuring Standard IPv6 ACLs 671 Configuring Extended IPv6 ACLs 674 Examples of Extended IPv6 ACLs 676 Practice Building ipv6 access-list Commands 9781587205798_BOOK.indb xxviii 670 670 678 6/1/16 12:01 PM .

Passwords.xxix Other IPv6 ACL Topics 679 Implicit IPv6 ACL Rules 679 An Example of Filtering ICMPv6 NDP and the Negative Effects 679 How to Avoid Filtering ICMPv6 NDP Messages 683 IPv6 ACL Implicit Filtering Summary 684 IPv6 Management Control ACLs 685 Chapter Review 686 Part VI Review 688 Part VII Miscellaneous 691 Chapter 26 Network Management 692 “Do I Know This Already?” Quiz 692 Foundation Topics 694 Simple Network Management Protocol 694 SNMP Concepts 695 SNMP Variable Reading and Writing: SNMP Get and Set 696 SNMP Notifications: Traps and Informs 696 The Management Information Base Securing SNMP 697 698 Implementing SNMP Version 2c 699 Configuring SNMPv2c Support for Get and Set 699 Configuring SNMPv2c Support for Trap and Inform Verifying SNMPv2c Operation Implementing SNMP Version 3 SNMPv3 Groups 701 702 704 705 SNMPv3 Users. and Encryption Keys Verifying SNMPv3 707 708 Implementing SNMPv3 Notifications (Traps and Informs) Summarizing SNMPv3 Configuration IP Service Level Agreement An Overview of IP SLA 711 712 713 Basic IP SLA ICMP-Echo Configuration 714 Troubleshooting Using IP SLA Counters 715 Troubleshooting Using IP SLA History SPAN 716 718 SPAN Concepts 718 The Need for SPAN When Using a Network Analyzer SPAN Session Concepts 9781587205798_BOOK.indb xxix 710 719 720 6/1/16 12:01 PM .

xxx CCNA Routing and Switching ICND2 200-105 Official Cert Guide Configuring Local SPAN 721 SPAN Session Parameters for Troubleshooting 724 Choosing to Limit SPAN Sources 725 Chapter Review 726 Chapter 27 Cloud Computing 730 “Do I Know This Already?” Quiz 730 Foundation Topics 732 Cloud Computing Concepts 732 Server Virtualization 732 Cisco Server Hardware 732 Server Virtualization Basics 733 Networking with Virtual Switches on a Virtualized Host 735 The Physical Data Center Network 736 Workflow with a Virtualized Data Center 737 Cloud Computing Services 739 Private Cloud 739 Public Cloud 741 Cloud and the “As a Service” Model 741 Infrastructure as a Service 742 Software as a Service 743 (Development) Platform as a Service 743 WAN Traffic Paths to Reach Cloud Services 744 Enterprise WAN Connections to Public Cloud 744 Accessing Public Cloud Services Using the Internet 745 Pros and Cons with Connecting to Public Cloud with Internet Private WAN and Internet VPN Access to Public Cloud 746 Pros and Cons with Connecting to Cloud with Private WANs Intercloud Exchanges A Scenario: Branch Offices and the Public Cloud Branch Offices with Internet and Private WAN Virtual Network Functions and Services 749 749 Migrating Traffic Flows When Migrating to Email SaaS 750 751 752 Virtual Network Functions: Firewalls and Routers 752 754 Address Assignment Services and DHCP NTP 747 748 Summarizing the Pros and Cons of Public Cloud WAN Options DNS Services 745 756 757 Chapter Review 758 9781587205798_BOOK.indb xxx 6/1/16 12:01 PM .

and Management Planes 762 The Data Plane 762 The Control Plane 763 The Management Plane 764 Cisco Switch Data Plane Internals 765 Controllers and Network Architecture 766 Controllers and Centralized Control The Southbound Interface 767 The Northbound Interface 768 SDN Architecture Summary 766 770 Examples of Network Programmability and SDN Open SDN and OpenFlow 770 771 The OpenDaylight Controller Cisco Open SDN Controller 771 772 The Cisco Application Centric Infrastructure The Cisco APIC Enterprise Module Comparing the Three Examples 773 774 776 Cisco APIC-EM Path Trace ACL Analysis Application APIC-EM Path Trace App 777 777 APIC-EM Path Trace ACL Analysis Tool Timing and Exam Topic Chapter Review Part VII Review 778 778 780 Part VIII Final Prep 783 Chapter 29 Final Review 784 Advice About the Exam Event 784 Learn the Question Types Using the Cisco Certification Exam Tutorial 784 Think About Your Time Budget Versus Number of Questions 785 A Suggested Time-Check Method 786 Miscellaneous Pre-Exam Suggestions 786 Exam-Day Advice 787 Reserve the Hour After the Exam in Case You Fail 788 9781587205798_BOOK.xxxi Chapter 28 SDN and Network Programmability 760 “Do I Know This Already?” Quiz 761 Foundation Topics 762 SDN and Network Programmability Basics 762 The Data. Control.indb xxxi 6/1/16 12:01 PM .

indb xxxii 6/1/16 12:01 PM .xxxii CCNA Routing and Switching ICND2 200-105 Official Cert Guide Exam Review 788 Take Practice Exams 789 Practicing Taking the ICND2 or CCNA R&S Exam Advice on How to Answer Exam Questions Taking Other Practice Exams 792 Find Knowledge Gaps Through Question Review Practice Hands-On CLI Skills 792 794 Review Mind Maps from Part Review Do Labs 790 790 795 795 Assess Whether You Are Ready to Pass (and the Fallacy of Exam Scores) 796 Study Suggestions After Failing to Pass 797 Other Study Tasks 798 Final Thoughts 799 Part IX Appendixes 801 Appendix A Numeric Reference Tables 803 Appendix B CCNA ICND2 200-105 Exam Updates 810 Glossary 813 Index 852 DVD Appendixes Appendix C Answers to the “Do I Know This Already?” Quizzes Appendix D Practice for Chapter 16: Basic IPv4 Access Control Lists Appendix E Mind Map Solutions Appendix F Study Planner Appendix G Learning IPv4 Routes with RIPv2 Appendix H Understanding Frame Relay Concepts Appendix I Implementing Frame Relay Appendix J IPv4 Troubleshooting Tools Appendix K Topics from Previous Editions Appendix L Exam Topic Cross Reference 9781587205798_BOOK.

9781587205798_BOOK. To start the registration process.ciscopress. Enter the product ISBN 9781587205798 and click Submit.indb xxxiii 6/1/16 12:01 PM . simply register your product.xxxiii Reader Services To access additional content for this and log in or create an account*. *Be sure to check the box that you would like to hear from us to receive exclusive discounts on future editions of this product. After the process is complete. go to www. you will find any available bonus content under Registered Products.

■ Square brackets ([ ]) indicate an optional element. boldface indicates commands that are manually input by the user (such as a show command).xxxiv CCNA Routing and Switching ICND2 200-105 Official Cert Guide Icons Used in This Book Printer PC Laptop Server Phone IP Phone Router Switch Frame Relay Switch Cable Modem Access Point ASA DSLAM WAN Switch CSU/DSU Hub PIX Firewall Bridge Layer 3 Switch Network Cloud Ethernet Connection Serial Line Virtual Circuit Ethernet WAN Wireless Command Syntax Conventions The conventions used to present command syntax in this book are the same conventions used in the IOS Command Reference. ■ Braces ({ }) indicate a required choice. In actual configuration examples and output (not general command syntax). 9781587205798_BOOK.indb xxxiv 6/1/16 12:01 PM . ■ Vertical bars (|) separate alternative. The Command Reference describes these conventions as follows: ■ Boldface indicates commands and keywords that are entered literally as shown. ■ Braces within brackets ([{ }]) indicate a required choice within an optional element. mutually exclusive elements. ■ Italic indicates arguments for which you supply actual values.

the 200-125 CCNA R&S exam is the seventh separate version of the exam (which warrants a different exam number). In many geographies and markets around the world. early in the year 2016.indb xxxv 6/1/16 12:01 PM . Cisco certification makes perfect sense. you’ve probably already decided to go for your Cisco certification. networking equals Cisco.Introduction About the Exams Congratulations! If you’re reading far enough to look at this book’s Introduction. and 200-125 CCNA exams. dating back to 1998. with more than 80 percent market share in some markets. CCENT 100-105 ICND1 200-105 ICND2 200-125 CCNA Figure I-1 CCNA Routing and Switching (CCNA R&S) Cisco Entry-Level Certifications and Exams Note that Cisco has begun referencing some exams with a version number on some of their websites. but you do not when working through the single-exam (200-125) option. and registering for the test. and the related 100-105 ICND1. Both paths cover the same exam topics. 200-105 ICND2. The CCENT certification requires a single step: pass the ICND1 exam. or just pass the CCNA exam. However. you need to know Cisco. Cisco has a ridiculously high market share in the router and switch marketplace. as shown in Figure I-1: pass both the ICND1 and ICND2 exams. 9781587205798_BOOK. when looking for information. To make sure you reference the correct exam. If that form holds true. the exams in Figure I-1 will likely be called version 3 (or v3 for short). Simple enough. but the two-exam path does so spread over two exams rather than one. just make sure to use the correct exam number as shown in the figure. If you want to be taken seriously as a network engineer. Most everyone new to Cisco certifications begins with either CCENT or CCNA Routing and Switching (CCNA R&S). using forums. Cisco gives you two options to achieve CCNA R&S certification. the paths to certification are not quite obvious at first. If you want to succeed as a technical person in the networking industry at all. You also pick up the CCENT certification by going through the two-exam path. Historically. The Exams to Achieve CCENT and CCNA R&S Cisco announced changes to the CCENT and CCNA Routing and Switching certifications.

The question types are ■ Multiple-choice. Cisco tells the world the specific topics on each of their certification exams. At the testing center. Although the first four types of questions in the list should be familiar to anyone who has taken standardized tests or similar tests in school.” This tool walks through each type of question Cisco may ask on the exam. you see a network topology. single-answer ■ Multiple-choice. people would try to get more information about what would be on the exams. someone would always ask. and what to not study at all. Cisco wants the public to know both the variety of topics 9781587205798_BOOK. Your job is to fix a problem with the configuration.xxxvi CCNA INTRO Official Exam Certification Guide Types of Questions on the Exams The ICND1. and can access the devices. In particular: ■ Sim questions: You see a network topology. whenever the teacher announced that we were having a test soon. and can access the and searching for “exam tutorial. and CCNA R&S exams all follow the same general format. and your verification and troubleshooting skills with simlet questions. At heart. a lab scenario. What’s on the CCNA Exams…and in the Book? Ever since I was in grade school. which you can find by going to Cisco. Before the exam timer begins. For every Cisco certification exam. what to study a little.indb xxxvi 6/1/16 12:01 PM . so that you control and use simulated Cisco devices. multiple-answer ■ Testlet (one scenario with several multiple-choice questions) ■ Drag-and-drop ■ Simulated lab (sim) ■ Simlet You should take the time to learn as much as possible by using the Cisco Certification Exam Tutorial. “What’s on the test?” Even in college. the last two types are more common to IT tests and Cisco exams in particular. ICND2. you also see several multiple-choice questions. Anyone who has user-level skills in getting around a PC should have no problems with the testing environment. However. You can find out more about what’s on the exam from two primary sources: this book and the Cisco website. like a testlet. Using these two question styles with the simulator enables Cisco to test your configuration skills with sim questions. a lab scenario. the goal is to know what to study hard. you have a chance to do a few other tasks on the PC. Like a sim question. you can take a sample quiz just to get accustomed to the PC and the testing engine. The Cisco Published Exam Topics First. for instance. Instead of changing/fixing the configuration. you sit in a quiet room with a PC. ■ Simlet questions: This style combines sim and testlet question formats. Both use a network simulator to ask questions. you answer questions about the current state of the network.

and how Cisco intends the exam topics to be a set of general guidelines for the exams. Although very useful. you should be able to not only configure IPv4 addresses and subnets. Just go to http://www. Note that this book lists those same exam topics in Appendix L. verify. This Book: About the Exam Topics This book provides a complete study system for the Cisco published exam topics for the ICND2 200-105 exam. and navigate until you see the exam topics.indb xxxvii 6/1/16 12:01 PM . verify. And if to do that you need to understand concepts and need to have other knowledge. but read the short material above the exam topics as listed at the Cisco web page for each certification and the list of exam topics would take about five pages of this book if laid out in a list. which describes one of the most important topics in both CCENT and CCNA R&S: Configure. “Exam Topic Cross Reference. and troubleshoot. the ICND1 100-105 exam topics list has 41 primary exam topics (topics with verbs). look for the CCENT and CCNA Routing and Switching pages. for content. CCNA = ICND1 + ICND2. those details are implied. consider the following exam topic. In short. The Cisco exam topics provide the definitive list of topics and skill levels required by Cisco for the exams. and the CCNA 200-125 single-exam path to CCNA. The CCENT/CCNA ICND1 100-105 Official Cert Guide (and ICND1 100105 exam topics) covers about half of the topics listed for the CCNA 200-125 exam. For those of you thinking more specifically about the CCNA R&S certification. they also list the depth to which you must master the topic. The exam questions will attempt to assess whether you can configure. verify. and this book (and the ICND2 200-105 exam topics) covers the other half. Cisco does more than just list the topic (for example. this book covers about one-half of the CCNA exam topics. and troubleshoot). So.Introduction xxxvii and what kinds of knowledge and skills are required for each topic. and troubleshoot IPv4 addressing and subnetting Note that this one exam topic has three verbs (configure. For example. and to troubleshoot problems when it is not working. But the list of exam topics provides only a certain level of depth. and the other with a list of chapters in this book with the corresponding exam topics included in each chapter. IPv4 addressing). cisco. Look for notices about the use of unscored items.” This PDF appendix lists two cross references: one with a list of the exam topics in the order in which Cisco lists them on their website. The primary exam topics each list one or more verbs that describe the skill level required. You should take the time to not only read the exam topics. but also understand them well enough to verify that the configuration works. 9781587205798_BOOK. All the topics in this book either directly relate to some ICND2 exam topic or provide more basic background knowledge for some exam topic. For example. The scope of the book is defined by the exam topics. plus additional subtopics that provide more details about that technology area.

. the Key Topic icon appears next to the most important items. the technology content in the chapter). about three-quarters of the chapter is about the technology. or. verification. use the Chapter Review tasks to start working on mastering your memory of the facts and skills with configuration. including the following: ■ Review Key Topics: In the “Foundation Topics” section. ■ Chapter Review: This section includes a list of study tasks useful to help you remember concepts.indb xxxviii 6/1/16 12:01 PM . ■ Foundation Topics: This is the heading for the core content section of the chapter. and about one-quarter is for the related study features. organized for reading and study as follows: ■ “Do I Know This Already?” quiz: Each chapter begins with a prechapter quiz.xxxviii CCNA Routing and Switching ICND2 200-105 Official Cert Guide Book Features This book (and the related CCENT/CCNA ICND1 100-105 Official Cert Guide) goes beyond what you would find in a simple technology book. And because the book organizes your study by chapter. It gives you a study system designed to help you not only learn facts but also to develop the skills you need to pass the exams. and determine how to approach reading the Foundation Topics (that is. in the technology chapters of the book. part. with lists and tables for comparisons. It also highlights the most important topics in each chapter as key topics. You can use the score to determine whether you already know a lot. Most of the book’s features tie in some way to the need to study beyond simply reading the “Foundation Topics” section of each chapter. DIKTA Quiz High Score Take Quiz Low Score Figure I-2 Foundation Topics Chapter Review (Skim) Foundation Topics (Read) Foundation Topics 1) In-Chapter. and troubleshooting. each “Chapter Review” section presents a variety of other book features. The “Foundation Topics” section of each chapter contains rich content to explain the topics on the exam and to show many examples. To do that. Figure I-2 shows how each chapter uses these three key elements. and for final review. While all 9781587205798_BOOK. 2) Companion Website 3) DVD Three Primary Tasks for a First Pass Through Each Chapter In addition to these three main chapter features. and then by part (a part contains multiple chapters). Chapter Features and How to Use Each Chapter Each chapter of this book is a self-contained short course about one topic area.. When finished with the Foundation Topics. so you know what to master first in your study. and practice skills-based content in the chapter. or not so much. and then a final review at the end of the book. You start with the “Do I Know This Already?” (DIKTA) quiz. The rest of this section explains these book features. connect ideas. This section makes extensive use of figures. for the purpose of later review and mastery. the next section of this Introduction discusses the book features introduced by chapter.

Figure I-3 lists the titles of the parts and identifies the chapters in those parts by chapter numbers. so these items are noted as key topics.indb xxxix The Book Parts and Corresponding Chapter Numbers 6/1/16 12:01 PM . and then reveals the completed table. ■ Command References: Some book chapters cover a large number of router and switch commands. The Part Review also suggests using the Pearson IT Certification Practice Test (PCPT) exam software that comes with the book. of course. but also use them for study— just cover one column of the table. The Part Review element that comes at the end of each book Part suggests that you repeat the DIKTA questions. The Chapter Review refers you to these other tools. scan the chapter for these items to review them. 6 IPv6 (22-25) 7 Miscellaneous (26-28) 4 IPv4 Services: ACLs and QoS (16-18) 5 IPv4 Routing and Troubleshooting (19-21) 3 Wide Area Networks (13-15) 2 IPv4 Routing Protocols (7-12) 1 Ethernet LANs (1-6) Figure I-3 9781587205798_BOOK. ■ Complete Tables from Memory: Instead of just rereading an important table of information.” “verify. more important to learn.Introduction xxxix content matters. However. Use these tables for reference.” and “troubleshoot”. all these refer to skills you should practice at the command-line interface (CLI) of a router or switch. Make sure you have a good understanding of each term. Each part contains a number of related chapters. This section includes reference tables for the commands used in that chapter. you do need to understand each term well enough to understand exam questions and answers. ■ Review DIKTA Questions: Re-answering the DIKTA questions from the chapter is a useful way to review facts. The “Review Key Topics” section lists the key topics in a table. This section lists the key terminology from the chapter. for extra practice in answering multiple-choice questions on a computer. some is. some tables have been marked as memory tables. These tables exist in the Memory Table app that is available on the DVD and from the companion website. so you can work on memorizing the content. along with an explanation. The app shows the table with some content removed. ■ Key Terms You Should Know: You do not need to be able to write a formal definition of all terms from scratch. and see how much you can remember and complete mentally. Part Features and How to Use Part Review The book organizes the chapters into seven parts. ■ Labs: Many exam topics use the verbs “configure. The Introduction’s section titled “About Building Hands-On Skills” discusses your options. and use the DVD Glossary to cross-check your own mental definitions. or needs more review to master.

to connect show commands and the related networking concepts. the Part Review includes some tasks meant to help pull the ideas together from this larger body of work. The process of creating mind maps helps you build mental connections. to help you think about topics from multiple chapters. many “Part Review” sections have you perform other tasks with book features mentioned in the “Chapter Review” section: repeating DIKTA quiz questions. labs that would be more appropriate for this stage of study and review. (You can take simulated ICND1 and CCNA R&S exams with the DVD in the CCENT/CCNA ICND1 100-105 Official Cert Guide. much like the “Chapter Review” section at the end of each chapter.) 9781587205798_BOOK. this book. as a whole. However. To that end. Chapter 29 focuses on a three-part approach to helping you pass: practicing your skills. ■ Mind Maps: Mind maps are graphical organizing tools that many people find useful when learning and processing how concepts fit together. including the following: ■ DVD-based practice exams: The companion DVD contains the powerful Pearson IT Certification Practice Test (PCPT) exam engine. The Part Review elements make use of mind maps in several ways: to connect concepts and the related configuration commands.xl CCNA Routing and Switching ICND2 200-105 Official Cert Guide Each book part ends with a “Part Review” section that contains a list of activities for study and review.indb xl 6/1/16 12:01 PM . along with a much larger set of practice questions.” lists a series of preparation tasks that you can best use for your final preparation before taking the exam. see the section “About Mind Maps” later in this Introduction. These questions tend to connect multiple ideas together. “Final Review. (Check out the later section “About Building Hands-On Skills” for information about lab options. You can take simulated ICND2 exams. and uncovering your weak spots. Final Review Chapter 29. with the DVD and activation code included in this book. as well as CCNA exams. practicing answering exam questions. The following list explains the types of tasks added to each Part Review beyond the types mentioned for the Chapter Review: ■ Answer Part Review Questions: The books come with exam software and databases of questions. (For more information about mind maps. because the Part Review takes place after completing a number of chapters. has additional study resources. One database holds questions written specifically for Part Reviews. Chapter 29 uses the same familiar book features discussed for the Chapter Review and Part Review elements. reviewing key topics. and doing more lab exercises. and even to connect terminology. and to build the skills needed for the more challenging analysis questions on the exams. Other Features In addition to the features in each of the core chapters.) In addition to these tasks.) ■ Labs: Each “Part Review” section will direct you to the kinds of lab exercises you should do with your chosen lab product.

right now. videos. EIGRP. ■ CCNA Simulator: If you are looking for more hands-on practice. you might want to consider purchasing the CCNA Network Simulator. ■ Companion website: The website http://www. all Chapter Review activities used only the book chapter. Basically. to experience the Cisco CLI. ■ Author’s website and blogs: I maintain a website that hosts tools and links that are useful when studying for CCENT and CCNA. and other certification preparation tools from the industry’s best authors and trainers. with links to the pages with the labs related to this book. certskills. Start at http://www. you also receive additional practice test questions and enhanced practice test features. PDF (for reading on your computer).indb xli 6/1/16 12:01 PM .com/networksimulator or other retail outlets. In the past. EIGRP metrics. most every activity that can be done in the “Chapter Review” sections can now be done with an application. I have created a mapping guide that maps each of the labs in the simulator to the specific sections in these CCNA cert guides. EPUB (for reading on your tablet. and links to my CCENT Skills blog and CCNA Skills study pages that correspond to each chapter of this book and the ICND1 book. plus PPP and CHAP. Readers tell us they find that content useful. You can get this mapping guide for free on the Extras tab of the companion website. This offer allows you to purchase the CCNA Routing and Switching ICND2 200-105 Official Cert Guide Premium Edition eBook and Practice Test at a 70 percent discount off the list price. ■ eBook: If you are interested in obtaining an eBook version of this title. ■ PearsonITCertification. we have included a special offer on a coupon card inserted in the DVD sleeve in the back of the The website http://www. but the content is static. or the chapter plus a DVD-only appendix. Check out the great CCNA articles. Just install it from the DVD in the back of this book. No need to go buy real gear or buy a full simulator to start learning the CLI. blogs. ■ Mentoring Videos: The DVD included with this book includes four other instructional videos about the following topics: OSPF. The apps can be found both on the DVD that comes with the book and on the book’s 9781587205798_BOOK.Introduction xli ■ CCNA ICND2 Simulator Lite: This lite version of the best-selling CCNA Network Simulator from Pearson provides you with a means. or Nook or other eReader). and Mobi (the native Kindle version). This book and the CCENT/CCNA ICND1 100-105 Official Cert Guide are the first Cisco Press Cert Guides with extensive interactive applications. To help you with your studies. The site lists information to help you build your own lab. A Big New Feature: Review Applications One of the single biggest new features of this edition of the book is the addition of study apps for many of the Chapter Review activities. Check this site regularly for new and updated postings written by the author that provide further insight into the more troublesome topics on the exam.ciscopress. mobile device. click the Blog tab for a page about the blogs in particular. In addition to three versions of the eBook. You can purchase a copy of this software from Pearson at is a great resource for all things IT-certification posts up-to-the-minute materials that further clarify complex exam topics.

all chapter review activities use the book chapter plus appendixes. Table I-1 summarizes these new applications and the traditional book features that cover the same content. you have all the content on the DVD. ■ Untethered from book/DVD: Because these apps are available on the book’s companion website in addition to the DVD. we want to increase the number of people using the review tools. If you buy the print book. and review content from one of your recently finished chapters. interactive experience that you can easily run over and over. but static. Just spin the DVD and use the disk menu (which should automatically start) to explore all the content. one with completed tables) Key Terms Listed in each “Chapter Review” section. or clicking inside an app to navigate. flip pages to find Key Topics Table app Config Checklist Just one of many types of key topics Config Checklist app Memory Table Two static PDF appendixes (one with Memory Table app sparse tables for you to complete. with the Glossary in the back of the book Glossary Flash Cards app IPv4 ACL Practice A static PDF appendix (D) with practice problems An interactive app that asks the same problems as listed in the appendix How to Get the Electronic Elements of This Book Traditionally. to help keep you focused on the activity. ■ Convenient: When you have a spare 5–10 minutes. these new apps provide you with an easy-to-use. But most of that content is static—useful. Table I-1 Book Features with Both Traditional and App Options Feature Traditional App Key Topics Table with list. Tactile learners may do better by at least typing answers into an app. and make them both more useful and more interesting. On the DVD you can find the apps under the “Chapter and Part Review” tab. with the appendixes often being located on the DVD. you can access your review activities from anywhere— no need to have the book or DVD with you.indb xlii 6/1/16 12:01 PM . So. but that not everyone uses them consistently. ■ Good for tactile learners: Sometimes looking at a static page after reading a chapter lets your mind wander. 9781587205798_BOOK. go to the book’s website. Our in-depth reader surveys show that readers who use the Chapter Review tools like them. The advantages of using these apps are as follows: ■ Easier to use: Instead of having to print out copies of the appendixes and do the work on paper.xlii CCNA Routing and Switching ICND2 200-105 Official Cert Guide companion website. and have a DVD drive.

“Miscellaneous LAN Topics. “Understanding OSPF Concepts.” explains the concepts and configuration surrounding virtual LANs. Chapters 1 through 28. ■ Chapter 5. and Appendixes This book contains 28 core chapters. your book will automatically be registered on your account page. AAA authentication.” shows how to configure and verify STP on Cisco switches. “VLAN Trunking Protocol. ■ Chapter 4. simply go to http://www.” shows how to configure. ■ Chapter 6. Simply go to your account page. and select Access Bonus Content to access the book’s companion website.” discusses the concepts behind IEEE Spanning Tree Protocol (STP) and how it makes some switch interfaces block frames to prevent frames from looping continuously around a redundant switched LAN. “LAN Troubleshooting. you can get the DVD files by registering your book on the Cisco Press website. click the Access Bonus Content link to get access to the book’s companion website. DHCP snooping.1x.indb xliii Chapter 7. go to your account page and click the Registered Products tab. Each core chapter covers a subset of the topics on the ICND2 exam. “Spanning Tree Protocol Implementation. the very last page of your eBook file will contain instructions for how to register the book and access the companion website. with Chapter 29 as the “Final Review” chapter. ■ Chapter 2. Layer 2 EtherChannel. and chassis aggregation. If you buy the CCNA Routing and Switching ICND2 200-105 Official Cert Guide Premium Edition eBook and Practice Test from Cisco Press. com/register and enter the ISBN of the print book: 9781587205798. and troubleshoot the use of VLAN Trunking Protocol (VTP) to define and advertise VLANs across multiple Cisco switches. After you have registered your book. The core chapters cover the following topics: Part I: Ethernet LANs ■ Chapter 1. LAN switching.” introduces the fundamental operation of the Open Shortest Path First (OSPF) protocol. switch stacking. discusses a variety of small topics. ■ Chapter 3. Part II: IPv4 Routing Protocols ■ 9781587205798_BOOK.Introduction xliii If you buy the print book but do not have a DVD drive. VLANs. Chapters. flooding link state data. “Spanning Tree Protocol Concepts. and VLAN trunking. click the Registered Products tab. neighbor relationships. From there. including: 802. focusing on link state fundamentals. including VLAN trunking. and calculating routes based on the lowest cost metric. “Implementing Ethernet Virtual LANs.” examines the most common LAN switching issues and how to discover those issues when troubleshooting a network. 6/1/16 12:01 PM . Book Organization. verify. To do so. The core chapters are organized into sections.” as the last chapter in the book specifically about LANs. The steps are the same as noted earlier for those who buy the print book but do not have a DVD drive. If you buy the eBook from some other bookseller. The chapter includes troubleshooting topics for STP/RSTP.ciscopress.

■ Chapter 17.” explains the core concepts of how to build a leased-line WAN and the basics of the two common data link protocols on these links: HDLC and PPP. “Private WANs with Ethernet and MPLS.” discusses a wide variety of concepts all related to the broad topic of QoS. focusing on EIGRP neighbor relationships. verify. for several technologies related to using the Internet to create a private WAN connection between different enterprise sites.” works through a variety of conceptual material. “Implementing EIGRP for IPv4. Layer 3 switching with SVIs. Layer 3 switching with routed ports.” explores the concepts behind building a WAN service using Ethernet through different Metro Ethernet services. “Quality of Service (QoS).” examines both named and numbered ACLs. “Understanding EIGRP Concepts.” discusses the need for a First Hop Redundancy Protocol (FHRP). ■ Chapter 15.” examines the basics of the Border Gateway Protocol (BGP) and its use between an enterprise and an ISP. “Implementing HSRP for First-Hop Routing. ■ Chapter 9. Part III: Wide Area Networks ■ Chapter 13.” takes the concepts discussed in the previous chapter and shows how to configure and verify those same features. and troubleshoot BGP in limited designs.” walks through the most common problems with IPv4 routing protocols.” examines how standard IP ACLs can filter packets based on the source IP address so that a router will not forward the packet.xliv CCNA Routing and Switching ICND2 200-105 Official Cert Guide ■ Chapter 8. “Advanced IPv4 Access Control Lists. including Router on a Stick (ROAS). and specifically how to configure. “Troubleshooting IPv4 Routing Protocols. while alternating between OSPF examples and EIGRP examples. plus some configuration and verification topics. “Basic IPv4 Access Control Lists. and troubleshoot Hot Standby Router Protocol (HSRP) 9781587205798_BOOK. “Implementing Point-to-Point WANs. ■ Chapter 12. as well as using Multiprotocol Label Switching (MPLS) VPNs. “IPv4 Routing in the LAN. and both standard and extended IP ACLs.indb xliv 6/1/16 12:01 PM .” takes the concepts discussed in the previous chapter and shows how to configure and verify those same features.” shows to a configuration and troubleshooting depth different methods to route between VLANs. ■ Chapter 20. ■ Chapter 14. “Implementing External BGP. showing how to configure. verify. ■ Chapter 10. Part IV: IPv4 Services: ACLs and QoS ■ Chapter 16.” introduces the fundamental operation of the Enhanced Interior Gateway Routing Protocol (EIGRP) for IPv4 (EIGRPv4). Part V: IPv4 Routing and Troubleshooting ■ Chapter 19. and how it quickly converges to alternate feasible successor routes. ■ Chapter 11. “Implementing OSPF for IPv4. “Private WANs with Internet VPNs. how EIGRP calculates metrics. and using Layer 3 EtherChannels. ■ Chapter 18.

“Numeric Reference Tables. ■ Chapter 27. in particular explaining the many study options available in the book. “Final Review. showing traditional configuration. then shows how to configure. ■ Chapter 28.” suggests a plan for final preparation once you have finished the core parts of the book. Part IX: Appendixes (In Print) ■ Appendix A.” looks at the most common IPv4 problems and how to find the root causes of those problems when troubleshooting. “SDN and Network Programmability. “Implementing OSPF for IPv6. Part VII: Miscellaneous ■ Chapter 26. This chapter explains the basic concepts and then generally discusses the impact that cloud computing has on a typical enterprise network.” is the other chapter that moves away from traditional CCNA R&S topics to discuss many concepts and terms related to how Software Defined Networking (SDN) and network programmability are impacting typical enterprise networks. and troubleshoot IPv6 ACLs. “Implementing EIGRP for IPv6. “Network Management. ■ Chapter 23.” is a place for the author to add book content mid-edition.” explores OSPFv3 and its use as an IPv6 routing protocol.” discusses several network management topics that Cisco did not choose to put into ICND1. Always check online for the latest PDF version of this appendix.” takes the EIGRP concepts discussed for IPv4 in Chapter 9 and shows how those same concepts apply to EIGRP for IPv6. and SPAN. verification.Introduction xlv ■ Chapter 21.” is one of two chapters about topics that strays from traditional CCNA R&S topics as one of the Cisco emerging technology topics. ■ Chapter 24. “IPv6 Routing Operation and Troubleshooting. 9781587205798_BOOK. verify. “IPv6 Access Control Lists.indb xlv 6/1/16 12:01 PM . verify.” examines the similarities and differences between IPv4 ACLs and IPv6 ACLs. ■ Chapter 25. including a binary-to-decimal conversion table and a list of powers of 2. Part VI: IPv6 ■ Chapter 22.” lists several tables of numeric information. It then shows how to configure. ■ Appendix B. “CCNA ICND2 200-105 Exam Updates. “Cloud Computing. ■ The Glossary contains definitions for all of the terms listed in the “Key Terms You Should Know” sections at the conclusion of Chapters 1 through 28. Part VIII: Final Prep ■ Chapter 29. namely: SNMP.” reviews IPv6 routing as discussed in the ICND1 book. “Troubleshooting IPv4 Routing. It then shows some of the most common problems with IPv6 routing and discusses how to troubleshoot these problems to discover the root cause. and troubleshooting topics. and troubleshoot EIGRP for IPv6. the appendix lists download instructions. IP SLA.

the concepts are still of interest to someone with the CCENT or CCNA certification.” shows an image of sample answers for all the partending mind map exercises. (This appendix is a copy of ICND1’s Chapter 19.” is a copy of the CCENT/CCNA ICND1 100-105 Official Cert Guide’s Appendix I.” is a collection of information about topics that have appeared on previous versions of the CCNA exams. focusing on the protocols and concepts rather than the configuration. and troubleshoot those same features.” explains how to build a Frame Relay WAN between routers. “Practice for Chapter 16: Basic IPv4 Access Control Lists. “Exam Topic Cross Reference. ■ Appendix E. verify. “Implementing Ethernet Virtual LANs” (Chapter 11 in the ICND1 100-101 book).) ■ Appendix I. “Answers to the ‘Do I Know This Already?’ Quizzes. where you can track your progress through your study. included here for those who might be interested. and is included with the ICND2 book for convenience.indb xlvi 6/1/16 12:01 PM .” explains how routers work together to find all the best routes to each subnet using a routing protocol. “Learning IPv4 Routes with RIPv2.” takes the concepts discussed in Appendix H and shows how to configure. (This appendix is a copy of ICND1’s Chapter 23.” is a spreadsheet with major study milestones. “IPv4 Troubleshooting Tools. This chapter also shows how to configure the RIPv2 routing protocol for use with IPv4. 9781587205798_BOOK.) ■ Appendix H.) ■ Appendix J. “Understanding Frame Relay Concepts. ■ Appendix L. ■ Appendix G. “Basic IPv4 Access Control Lists” (Chapter 25 in the ICND1 100-101 book).” includes the explanations to all the questions from Chapters 1 through 28.” provides some tables to help you find where each exam objective is covered in the book. included here for those who might be interested. “Implementing Frame Relay. “Mind Map Solutions. While you most likely will not encounter exam questions on these topics.xlvi CCNA Routing and Switching ICND2 200-105 Official Cert Guide Part X: DVD Appendixes The following appendixes are available in digital format on the DVD that accompanies this book: ■ Appendix C. “Topics from Previous Editions. ■ Appendix F. “Study Planner.” focuses on how to use two key troubleshooting tools to find routing problems: the ping and traceroute commands. (This chapter is a chapter that covers old exam topics from the previous edition of the book.) ■ Appendix K. These chapters include some topics that are listed in the exam topics of both exams: ■ Chapter 1. I designed several chapters to be used in both books. and is included with the ICND2 book for convenience. (This chapter is a chapter that covers old exam topics from the previous edition of the book. ■ Appendix D. ■ Chapter 16. ICND1 Chapters in this Book For this current edition of the ICND1 and ICND2 Cert Guides.

indb xlvii 6/1/16 12:01 PM . then you have all the material you need right here in this book. This short section explains why. I designed these four chapters for use in both books to be a help to those reading both books while avoiding any problems for those who might be reading only this ICND2 Cert Guide. If you did not read the ICND1 100101 book. In particular. which lists several contact details. two appendixes are here to aid the transition when Cisco announced the exams. or for those who want to read more broadly just for the sake of learning. I. PCPT has many options. Install the Pearson IT Certification Practice Test Engine and Questions This book. including the option to answer questions 9781587205798_BOOK. Appendixes H and I are copies of complete chapters about Frame Relay from the prior edition of this book. So. This material might be helpful to some instructors during the transition time for their courses. Cisco has traditionally had some topics that overlap between the two exams that make up the two-exam path to CCNA R&S. you can move more quickly through the above four chapters in this book. and K. You do not need to use these extra appendixes (G through K) to prepare for the ICND2 200-105 exam or the CCNA R&S 200-125 exam. but feel free to use them if you are interested. H. and this current pair of exams is no exception. Appendixes H. I included Appendixes G and J to aid that transition for those who buy the ICND2 200-105 Cert Guide but not the ICND1 100-105 Cert Guide. like many other Cisco Press books. and are part of the exam topics for the ICND1 100-105 exam. and Appendix K is a compilation of small topics I removed from the prior edition of this book when creating this current edition. Extra Content Found in DVD Appendixes Note that several appendixes on the DVD. contain extra content outside the ICND2 200-105 exam topics. ■ Chapter 21. make sure to note the final page of this introduction. First. “Advanced IPv4 Access Control Lists” (Chapter 26 in the ICND1 100-101 book). and K contain content that is no longer mentioned by the exam topics for the current exams.Introduction xlvii ■ Chapter 17. includes the rights to use the Pearson IT Certification Practice Test (PCPT) software. Appendixes G (about RIP) and J (about ping and traceroute) are copies of two chapters in the ICND1 100-105 book. J. “Troubleshooting IPv4 Routing” (Chapter 24 in the ICND1 100-101 book). for those of you who have already read the ICND1 100-101 book. but you may also skip these topics and refer back to them later. You may read these when you first use the book. These two chapters might be particularly useful for anyone who was far along in their studies on the date when Cisco announced the ICND1 100-105 and ICND2 200-105 exams in 2016. including how to get in touch with Cisco Press. Reference Information This short section contains a few topics available for reference elsewhere in the book. namely G. I. Three other appendixes are included for instructors who use these books for classes. along with rights to use some exam questions related to this book. as well as for the occasional reader who is mostly interested in the technology instead of the certification.


CCNA Routing and Switching ICND2 200-105 Official Cert Guide
in study mode, so you can see the answers and explanations for each question as you go
along; the option to take a simulated exam that mimics real exam conditions; and the option
to view questions in flash card mode, where all the answers are stripped out, challenging
you to answer questions from memory.
You should install PCPT so it is ready to use even for the earliest chapters. This book’s Part
Review sections ask you specifically to use PCPT, and you can even take the DIKTA chapter quizzes using PCPT.
NOTE The right to use the exams associated with this book is based on an activation code.
For those with a paper book, the code is in the DVD sleeve at the back of the book. (Flip
over the paper with the exam activation code to find a one-time-use coupon code for 70
percent off the purchase of the CCNA Routing and Switching ICND2 200-105 Official
Cert Guide, Premium Edition eBook and Practice Test.) For those who purchase the
Premium Edition eBook and Practice Test directly from the Cisco Press website, the activation code will be populated on your account page after purchase. For those who purchase
a Kindle edition, the access code will be supplied directly from Amazon. Note that if you
purchase an eBook version from any other source, the practice test is not included, as other
vendors are not able to vend the required unique access code. Do not lose the activation

PCPT Exam Databases with This Book
This book includes an activation code that allows you to load a set of practice questions.
The questions come in different exams or exam databases. When you install the PCPT software and type in the activation code, the PCPT software downloads the latest version of all
these exam databases. And with the ICND2 book alone, you get six different “exams,” or
six different sets of questions, as listed in Figure I-4.
DIKTA (“Book”)

ICND2 Exam #1

CCNA Exam #1

Part Review

ICND2 Exam #2

CCNA Exam #2

Figure I-4

PCPT Exams/Exam Databases and When to Use Them

You can choose to use any of these exam databases at any time, both in study mode and
practice exam mode. However, many people find it best to save some of the exams until
exam review time, after you have finished reading the entire book. Figure I-4 begins to suggest a plan, spelled out here:

During Part Review, use PCPT to review the DIKTA questions for that part, using study

During Part Review, use the questions built specifically for Part Review (the Part Review
questions) for that part of the book, using study mode.

Save the remaining exams to use with the “Final Review” chapter at the end of the book;
if preparing for the ICND2 exam, use those practice exams, but if preparing for the
CCNA exam, use those exams.

9781587205798_BOOK.indb xlviii

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Introduction xlix
The two modes inside PCPT give you better options for study versus practicing a timed
exam event. In study mode, you can see the answers immediately, so you can study the
topics more easily. Also, you can choose a subset of the questions in an exam database; for
instance, you can view questions from only the chapters in one part of the book.
PCPT practice mode lets you practice an exam event somewhat like the actual exam. It
gives you a preset number of questions, from all chapters, with a timed event. Practice exam
mode also gives you a score for that timed event.

How to View Only DIKTA Questions by Chapter or Part
Most chapters begin with a DIKTA quiz. You can take the quiz to start a chapter, take it
again during Chapter Review for more practice, and, as suggested in the “Part Review” sections, repeat the questions for all chapters in the same part.
You can use the DIKTA quiz as printed in the book, or use the PCPT software. The book
lists the questions, with the letter answers on the page following the quiz. Appendix C, on
the DVD, lists the answers along with an explanation; you might want to keep that PDF
Using PCPT for these questions has some advantages. It gives you a little more practice in
how to read questions from testing software. Also, the explanations to the questions are
conveniently located in the PCPT software.
To view these DIKTA questions inside the PCPT software, you need to select Book
Questions, which is the way PCPT references questions found inside the printed book.
Then you have to deselect all chapters (with a single click), and then select one or more
chapters, as follows:
Step 1.

Start the PCPT software.

Step 2.

From the main (home) menu, select the item for this product, with a name like
CCNA Routing and Switching ICND2 200-105 Official Cert Guide, and click
Open Exam.

Step 3.

The top of the next window that appears should list some exams; check the
ICND2 Book Questions box, and uncheck the other boxes. This selects the
“book” questions (that is, the DIKTA questions from the beginning of each

Step 4.

On this same window, click at the bottom of the screen to deselect all objectives (chapters). Then select the box beside each chapter in the part of the
book you are reviewing.

Step 5.

Select any other options on the right side of the window.

Step 6.

Click Start to start reviewing the questions.

How to View Part Review Questions
The exam databases you get with this book include a database of questions created solely
for study during the Part Review process. DIKTA questions focus more on facts, to help

9781587205798_BOOK.indb xlix

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CCNA Routing and Switching ICND2 200-105 Official Cert Guide
you determine whether you know the facts contained within the chapter. The Part Review
questions instead focus more on application of those facts to typical real scenarios, and
look more like real exam questions.
To view these questions, follow the same process as you did with DIKTA/book questions,
but select the Part Review database rather than the book database. PCPT has a clear name
for this database: Part Review Questions.

About Mind Maps
Mind maps are a type of visual organization tool that you can use for many purposes. For
instance, you can use mind maps as an alternative way to take notes.
You can also use mind maps to improve how your brain organizes concepts. Mind maps
improve your brain’s connections and relationships between ideas. When you spend time
thinking about an area of study, and organize your ideas into a mind map, you strengthen
existing mental connections and create new connections, all into your own frame of reference.
In short, mind maps help you internalize what you learn.
Each mind map begins with a blank piece of paper or blank window in a mind mapping
application. You then add a large central idea, with branches that move out in any direction.
The branches contain smaller concepts, ideas, commands, pictures…whatever idea needs to
be represented. Any concepts that can be grouped should be put near each other. As need
be, you can create deeper and deeper branches, although for this book’s purposes, most
mind maps will not go beyond a couple of levels.
NOTE Many books have been written about mind maps, but Tony Buzan often gets credit
for formalizing and popularizing mind maps. You can learn more about mind maps at his
For example, Figure I-5 shows a sample mind map that begins to output some of the IPv6
content from Part VIII of the ICND1 book. You might create this kind of mind map when
reviewing IPv6 addressing concepts, starting with the big topic of “IPv6 addressing,” and
then writing down random terms and ideas. As you start to organize them mentally, you
draw lines connecting the ideas, reorganize them, and eventually reach the point where you
believe the organization of ideas makes sense to you.

Figure I-5

9781587205798_BOOK.indb l

Sample Mind Map

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and then check your answer versus the supplied answer. You job is to create the configuration. for mind mapping tools. introduced as a new feature in this edition of the and click from there. Note that the Config Lab posts should show an image like this in the summary: 9781587205798_BOOK. navigate to Hands On > Config Lab Both blogs are geared toward helping you pass the exams.indb li 6/1/16 12:01 PM . and the device (a router or switch) displays messages in response. in which combination. Finally. The Cisco CLI is a text-based command-and-response user interface. I hope you will make the effort to try these tools and see if they work well for you too. specifically the Cisco CLI. and you need to be able to navigate to the right place in the CLI to use those commands. To reach my blog sites for ICND1 content or for ICND2 content (two different blogs) and access the Config Labs feature. blog. the challenge level goes beyond just picking the right parameters on one command. navigate to Hands On > Config Lab blog.certskills. I have used Mind Node Pro on a Mac. which ones are required. this edition places the content not only outside the book but also on the author’s blog site. you can start at my blog launch site (blog. you need to know a lot of commands. you can just draw them on a blank piece of paper. which has free versions for Windows. helps provide that practice. So. and you have to decide what to configure on each device. The answer then shows a sample configuration. or find and download a mind map application.Introduction li Mind maps may be the least popular but most effective study tool suggested in this book. And getting good at that kind of task requires Wendell’s CCENT (ICND1): In the menus. Part of the skill you need to acquire is the ability to remember which configuration commands work together. This section walks through the options included in the book. and which ones are optional. About Building Hands-On Skills You need skills in using Cisco routers and Wendell’s CCNA (ICND2): In the menus. The Config Labs feature. typically on multiple devices. I personally find a huge improvement in learning new areas of study when I mind map. with some requirements. To answer sim and simlet questions on the exams. so feel free to look around. Config Lab Exercises Some router and switch features require multiple configuration commands. Each lab presents a sample lab topology. and we build the sample mind maps with XMIND. Linux. and OS X. You have to choose which commands to use.certskills. you type a command. Also for the first time. with a brief description of lab options outside the book.

So. The latest version of NetSim Lite includes labs associated with Part II of this book.lii CCNA Routing and Switching ICND2 200-105 Official Cert Guide Figure I-6 Config Lab Logo in the Author’s Blogs These Config Labs have several benefits. you have discovered a topic that you can now go back and reread to complete your knowledge. one reason that NetSim Lite comes on the DVD is that the publisher hopes you will buy the full product. NOTE The ICND1 and ICND2 books each contain a different version of the Sim Lite product. The good news is that you have a free and simple first step to experience the CLI: Install and use the Pearson NetSim Lite that comes with this book. If you bought both books. even if you do not use the full product. ■ Designed for idle moments: Each lab is designed as a 5. both good: Practice getting better and faster with basic configuration. without help. you are a step closer to being ready for the exam! ■ Blog format: Allows easy adds and changes by me. from any web browser.indb lii 6/1/16 12:01 PM . you should be able to do all the Config Labs. Part I includes concepts only. A Quick Start with Pearson Network Simulator Lite The decision of how to get hands-on skills can be a little scary at first. See the “Your Study Plan” element that follows the Introduction for more details about those review sections. make sure you install both Sim Lite products. each with labs that match the book content. which provides you with a means. ■ Two outcomes. untethered from the book or DVD. Either way. from your phone or tablet. Just install NetSim Lite from the DVD in the back of this book. right now. and with 10-minute exercise if all you are doing is typing in a text editor or writing your answer on paper. or if you get lost. Note that the blog organizes these Config Lab posts by book chapter. including the following: ■ Untethered and responsive: Do them from anywhere. make sure and use NetSim Lite to learn the basics of the CLI to get a good start. No need to go buy real gear or buy a full simulator to start learning the CLI. This book comes with a lite version of the best-selling CCNA Network Simulator from Pearson. and easy comments by you. Of course. to experience the Cisco CLI. you can still learn from the labs that come with NetSim Lite while deciding about what options to pursue. However. ■ Self-assessment: As part of final review. with Part II being the first part with commands. so you can easily use these at both Chapter Review and Part Review. 9781587205798_BOOK.

Introduction liii The Pearson Network Simulator The Config Labs and the Pearson Network Simulator Lite both fill specific needs. ICND2 200-101. start the topology. Note that the Simulator and the books work on a different release schedule. the Simulator organizes the labs to match the book. the Simulator is still very useful. This simulator product simulates Cisco routers and switches so that you can learn for the CCENT and CCNA R&S certifications. Both have the same base code and same user Thankfully. you could even do the Config Lab exercises from my blog on that gear. and connect to real router and switch OS images. you need to make a decision for yourself. find that PDF at http:// www. You should plan to use some lab environment to practice as much CLI interaction as possible. the version of the Simulator available for purchase will be the Simulator created for the previous versions of the exams (ICND1 100-101. There is a full product for CCENT only. and another for CCNA R&S (which includes all the labs in the CCENT product.indb liii 6/1/16 12:01 PM . The single best option for lab work to do along with this book is the paid version of the Pearson Network Simulator. you need more than those two tools. First. If you have the right mix of gear. and check out the full product. Of course. So during that time. you can use real Cisco routers and switches. You can rent them for a fee. and consider all the options. new or used. Reader surveys tell us that those people who use the Simulator along with the book love the learning process. 9781587205798_BOOK. you can get a great idea of how the full Simulator product works by using the Pearson Network Simulator Lite product included with the book. This tool. and the same types of labs. the Virtual Internet Routing Lab (VIRL). Check out http://virl. But more importantly.ciscopress. in an offering called Cisco Learning Labs. Just look for the “Sort by Chapter” tab in the Simulator’s user interface. plus others for the ICND2 parts of the content). when you want to do labs while reading a chapter or doing Part Review. and rave about how the book and Simulator work well together. during the months in 2016 for which the available Simulator is the older edition listing the older exams in the title. You can buy them. For a time in 2016. and they both come with the book. or borrow them at work. and CCNA 200-120). Cisco offers a virtualization product that lets you run router and switch operating system (OS) images in a virtual environment. On a practical note. you still need hands-on experience. Try the Lite version. it focuses on learning for the exam by providing a large number of useful lab exercises. More Lab Options If you decide against using the full Pearson Network Simulator. You can even rent virtual Cisco router and switch lab pods from for more lets you create a lab topology. However. That product includes approximately 80 percent of the CLI topics in the ICND1 100-105 and ICND2 200-105 books. you will need to refer back to a PDF that lists those labs versus this book’s organization. or try and re-create examples from the book. However.

creating a virtual environment running real Cisco IOS. This is the CCNA and ICND2 certification book from the only Cisco-authorized publisher. You should always check http://www. 9781587205798_BOOK.indb liv 6/1/16 12:01 PM . This book does not tell you what option to use. but the next two are generally free to the user. submit them via http://www. but the real work is up to you! I trust that your time will be well spent. So. We at Cisco Press believe that this book certainly can help you achieve CCNA certification. but you should plan on getting some handson practice somehow. Cisco also makes a simulator that works very well as a learning tool: Cisco Packet Tracer. The CCNA ICND2 200-105 Official Cert Guide helps you attain CCNA Routing and Switching certification. and not for the general public. For More Information If you have any comments about the book. GNS3 is not a Cisco product. Cisco intends Packet Tracer for use by people currently enrolled in Cisco Networking Academy First. but with a different catch for each. Cisco might make changes that affect the CCNA certification from time to time. for the latest details. However. Just go to the and CCNA Routing and Switching ICND2 200-105 Official Cert Guide All these previously mentioned options cost some money. and cannot provide you with the IOS images for legal reasons. The important thing to know is that most people need to practice using the Cisco CLI to be ready to pass these exams. and type your definitely use Packet Tracer. GNS3 works somewhat like VIRL. if you are part of a Cisco Academy. select Contact Us.ciscopress.

9781587205798_BOOK.indb lv 6/1/16 12:01 PM .

This chapter briefly repeats the leased line concepts from the ICND1 book. with a focus on concepts and configuration. which of the following usually connects to a four-wire line provided by a telco? a. The final major section then discusses typical root causes of serial link problems and how to find those problems. “Do I Know This Already?” Quiz Take the quiz (either here. Table 13-1 “Do I Know This Already?” Foundation Topics Section-to-Question Mapping Foundation Topics Section Questions Leased-Line WANs with HDLC 1–2 Leased-Line WANs with PPP 3–6 Troubleshooting Serial Links 7 1. along with HDLC (and related) configuration. while using leased lines as part of larger discussions of IP routing.indb 328 In the cabling for a leased line. or use the PCPT software) if you want to use the score to help you decide how much time to spend on this chapter. The second major section discusses PPP. The first looks at leasedline WANS that use HDLC. to lay a foundation to discuss other concepts. an alternate data-link protocol that you can use instead of HDLC.0 WAN Technologies 3. The answers are at the bottom of the page following the quiz. More important. this chapter looks at the configuration. and the explanations are in DVD Appendix C and in the PCPT software. That simplicity allows the Cisco exams to discuss leased lines briefly for the ICND1 exam. and troubleshooting steps for leased lines that use the familiar High-level Data Link Control (HDLC) data-link protocol and the Point-to-Point Protocol (PPP). 9781587205798_BOOK. This chapter finally takes the discussion of leased-line WANs deeper than has been discussed so far. Switch serial interface 6/1/16 12:02 PM . Router serial interface with internal transceiver d.CHAPTER 13 Implementing Point-to-Point WANs This chapter covers the following exam topics: 3. at least to the depth required for the CCENT and CCNA R&S exams. by reviewing and adding details about the physical links themselves. This chapter breaks the material down into three major sections. verification. CSU/DSU c. Router serial interface without internal CSU/DSU b.1 Configure and verify PPP and MLPPP on WAN interfaces using local authentication Leased-line WANs—also known as serial links—require much less thought than many other topics.

c. encapsulation hdlc b. encapsulation ppp b. 5. rxload 1/255 Encapsulation PPP. DES Two routers have no initial configuration whatsoever. Two routers connect with a serial link. The link is currently working using PPP. no encapsulation hdlc c.) a. Which of the following commands are required in the R1 configuration for the link to reach a state in which R1 can ping R2’s serial IP address. line protocol is up Hardware is GT96K Serial Internet address is 192. clock rate d.2. ip address Consider the following excerpt from the output of a show command: Serial0/0/1 is up.168. MD5 b. 3. The interface currently cannot pass IPv4 traffic.) a. encapsulation cisco-hdlc c. IPCP.indb 329 a. The interface is using HDLC. Which of the following commands can be used to migrate to HDLC successfully? (Choose two answers. reliability 255/255. assuming that the physical back-to-back link physically works? (Choose two answers. DLY 20000 usec. The network engineer wants to migrate to use the Cisco-proprietary HDLC that includes a protocol type field. 6/1/16 12:02 PM .) 9781587205798_BOOK. loopback not set Which of the following are true about this router’s S0/0/1 interface? (Choose two answers. PAP c. each using its S0/0/0 interface. The link should be able to pass PPP frames at the present time. BW 1544 Kbit. The engineer wants to create a working PPP link by configuring both routers. encapsulation-type auto Which of the following PPP authentication protocols authenticates a device on the other end of a link without sending any password information in clear text? a. d.2.1/24 MTU 1500 bytes. 4. CHAP d. b. The interface is using PPP. They are connected in a lab using a DTE cable connected to R1 and a DCE cable connected to R2. no encapsulation ppp d. txload 1/255. with the DTE and DCE cables then connected to each other. LCP Open Open: CDPCP.

X bits/second R1 R2 X bits/second All the Time Figure 13-1 9781587205798_BOOK.2. ppp multilink while in serial interface configuration mode Consider the following excerpt from the output of a show interfaces command on an interface configured to use PPP: Serial0/0/1 is up. CHAP authentication failed. b. R1 and R2. Two routers.1/24 A ping of the IP address on the other end of the link fails. along with configuring CHAP configuration. The router on the other end of the link has been configured to use HDLC. line protocol is down Hardware is GT96K Serial Internet address is 192. The network engineer configures these links to be part of the same multilink PPP group. ip address address mask while in serial interface configuration mode c. each router can send at any time (full duplex). Both Directions.) a. Always On 6/1/16 12:02 PM . Which of the following are reasons for the failure. and OSPFv2 using interface configuration. c.330 CCNA Routing and Switching ICND2 200-105 Official Cert Guide 6. connect to each other using three serial links. ppp authentication chap while in multilink interface configuration mode d. 7. As shown in Figure 13-1. The CSU/DSU connected to the other router is not powered on. d. Which of the following answers list a configuration command along with the correct configuration mode for that command? (Choose two answers. Foundation Topics Leased-Line WANs with HDLC A physical leased-line WAN works a lot like in an Ethernet crossover cable connecting two routers. meaning that both routers send bits at the same speed. The IP address on the router at the other end of the link is not in subnet 192. e. IPv4. encapsulation ppp while in multilink interface configuration mode b.0/24. but with no distance limitations. None of the above.2.) a.168.indb 330 Leased Line: Same Speed.168. assuming that the problem listed in the answer is the only problem with the link? (Choose two answers. ip ospf 1 area 0 while in serial interface configuration mode e. The speed is also symmetric.

WAN link. D 5 B. Table 13-2 Name Different Names for a Leased Line Meaning or Reference Leased circuit. However. D 9781587205798_BOOK.points only. followed by the Layer 2 details. circuit circuit makes reference to the electrical circuit between the two endpoints. and then the router de-encapsulates the network layer packet. the term leased line refers to the fact that the company using the leased line does not own the line. routers also need to use a data link protocol on the WAN link to send bits over the link.544 megabits per second (1. LAN1 HDLC LAN2 PC1 PC2 R1 1 802. (Some older leased lines allowed more than two devices.3 Figure 13-2 IP Packet 802. However. first with the Layer 1 details. E 7 C.indb 331 6/1/16 12:02 PM . Point-to-point Refers to the fact that the topology stretches between two points. First.544 Mbps).) point line T1 A specific type of leased line that transmits data at 1. many people today use the generic term service provider to refer to a company that provides any form of WAN connectivity. as shown at Step 2 of Figure 13-2. point-to. but instead pays a monthly lease fee to use it. respectively. of leased-line WANs.3 Routers and Their Use of HDLC to Encapsulate Packets These first two figures review some of the Layer 1 and Layer 2 details.Chapter 13: Implementing Point-to-Point WANs 331 Although the leased line provides a physical layer bit transmission facility. As a result of their long history in the market. the networking world has used a large number of different terms. The story should be familiar by now: routers receive frames in LAN interfaces. you lease the service from a telephone company. Serial in this case refers to the fact that the bits flow serially and that routers use serial interfaces. serial line The words link and line are also often used as synonyms.3 R2 2 HDLC IP Packet HDLC 3 802. This first major section of this chapter begins by discussing these links again. C 3 C 4 A. Before forwarding the packet. The words line and circuit are often used as synonyms in telco terminology. Table 13-2 lists some of those names so that you can understand the different terms you will encounter in a real networking job. Layer 1 Leased Lines Leased lines have been around a long time. they still exist today as a WAN service. Often. including Internet services. D 6 A. or telco. the router encapsulates the packet inside a WAN data link protocol like High-level Data Link Control (HDLC). with no reference to any specific technology. and two link. Serial link.3 IP Packet 802. 13 Answers to the “Do I Know This Already?” quiz: 1 B 2 A. link Both these terms are very general. roughly 20 years longer than LANs. This section ends with an explanation of HDLC configuration details.


CCNA Routing and Switching ICND2 200-105 Official Cert Guide

The Physical Components of a Leased Line
To create a leased line, the telco must create some physical transmission path between the
two routers on the ends of the link. The physical cabling must leave the buildings where
each router sits. Then the telco must create the equivalent of a two-pair circuit from end
to end, with one circuit to send data in each direction (full duplex). Figure 13-3 shows one
such example, in which the telco uses a couple of traditional central office (CO) switches to
create a short leased line between two routers.
Customer Site1

Telco CO1

Telco CO2



Customer Site2




Figure 13-3

Possible Cabling Inside a Telco for a Short Leased Line

The details in the center of Figure 13-3 probably show more than you ever need to know
about leased-line WANs, at least from the enterprise customer perspective. More commonly, most network engineers think more about a leased line from the perspective of Figure
13-4, which shows a few key components and terms for the equipment on the ends of a
leased line, as follows:
Customer premises equipment (CPE): This telco term refers to the gear that sits at their
customers’ sites on the ends on the link.
Channel service unit/data service unit (CSU/DSU): This device provides a function
called clocking, in which it physically controls the speed and timing at which the router
serial interface sends and receives each bit over the serial cable.
Serial cable: This is a short cable that connects the CSU and the router serial interface.
Short Cables (Usually Less Than 50 Feet)
Long Cables (Can Be Several Miles Long)





Figure 13-4



Point-to-Point Leased Line: Components and Terminology

The CPE includes several separately orderable parts. When using an external CSU/DSU,
a serial cable must be used to connect the CSU to the router serial interface. These serial
interfaces usually exist as part of a removable card on the router, called either WAN interface cards (WIC), High-speed WICs (HWIC), or Network Interface Modules (NIM). Most

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Chapter 13: Implementing Point-to-Point WANs 333
of the serial interfaces use one style (size/shape) of physical connector called a smart serial
connector, whereas the CSU has one of several other types of connectors. So, when installing the leased line, the engineer must choose the correct cable type, with connectors to
match the WIC on one end and the CSU/DSU on the other. Figure 13-5 shows a drawing of
one type of serial cable, with the smart serial connector on the left, and the popular V.35
connector on the right. The figure shows a side view of the entire cable, plus direct views
into the connector on the ends of the cable.





Figure 13-5



Serial Cables Used Between a CSU and a Router

Today, many leased lines make use of Cisco WICs with an integrated CSU/DSU. That is, the
WIC hardware includes the same functions as a CSU/DSU, so an external CSU/DSU is not
needed. Compared to Figure 13-4, the external CSU/DSU and serial cable on each end are
not needed, with the cable from the telco connecting directly to the WIC.
Figure 13-6 shows a photo of a router with two NIM slots. Each slot currently shows a
faceplate with no NIM cards installed. The foreground of the figure shows a NIM with two
serial ports, with smart serial interfaces. The cable end on the left of the drawing in Figure
13-5 would attach to one of these smart serial ports on the NIM in Figure 13-6.

2 NIM Slots

(RJ-45 or SFP)

2-Port Serial NIM

Figure 13-6


Photo of Router with Serial NIM on the Right

Telcos offer a wide variety of speeds for leased lines. However, a telco customer cannot
pick just any speed. Instead, the speeds follow the standards of an age-old technology
called the T-carrier system.

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CCNA Routing and Switching ICND2 200-105 Official Cert Guide
Back in the 1950s and 1960s, the U.S.-based Bell companies developed and deployed digital
voice and the T-carrier system. As part of that work, they standardized different transmission speeds, including 64 Kbps, 1.544 Mbps, and 44.736 Mbps.
Those same Bell companies developed time-division multiplexing (TDM) technology that let
them combine multiples of these base speeds onto a single line. For instance, one popular
standard, a Digital Signal level 1 (DS1), or T1, combines 24 DS0s (at 64 Kbps) plus 8 Kbps
of overhead into one physical line that runs at 1.544 Mbps. However, to allow flexibility of
speeds offered to customers, the telco could install a T1 line to many sites, but run some
at slower speeds and some at faster speeds—as long as those speeds were multiples of 64
Now back to the idea of the speed of a leased line. What can you actually buy? Basically, at
slower speeds, you get any multiple of 64 Kbps, up to T1 speed. At faster speeds, you can
get multiples of T1 speed, up to T3 speed. Table 13-3 summarizes the speeds typically seen
in the United States, with a few from Europe.
Table 13-3

WAN Speed Summary

Names of Line

Bit Rate


64 Kbps

Fractional T1

Multiples of 64 Kbps, up to 24X

DS1 (T1)

1.544 Mbps (24 DS0s, for 1.536 Mbps, plus 8 Kbps overhead)

E1 (Europe)

2.048 Mbps (32 DS0s)

Fractional T3

Multiples of 1.536 Mbps, up to 28X

DS3 (T3)

44.736 Mbps (28 DS1s, plus management overhead)

E3 (Europe)

Approx. 34 Mbps (16 E1s, plus management overhead)

The Role of the CSU/DSU
For our last bit of discussion about WAN links in a working enterprise internetwork, next
consider the role of the CSU/DSU (called CSU for short). For the sake of discussion, the
next few paragraphs, leading up to Figure 13-7, assume a leased line with external
CSU/DSUs, like earlier in Figure 13-4.
The CSU sits between the telco leased line and the router; it understands both worlds and
their conventions at Layer 1. On the telco side, that means the CSU connects to the line
from the telco, so it must understand all these details about the T-carrier system, TDM,
and the speed used by the telco. On the router side of the equation, the CSU connects to
the router, with roles called the DCE and DTE, respectively. The CSU, acting as DCE (data
circuit-terminating equipment), controls the speed of the router serial interface. The router,
acting as DTE (data terminal equipment), is controlled by the clocking signals from the CSU
(DCE). That is, the CSU tells the router when to send and receive bits; the router attempts
to send and receive bits only when the DCE creates the correct electrical impulses (called
clocking) on the cable. Figure 13-7 shows a diagram of those main concepts of the role of
the CSU/DSU.

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you can create the equivalent of a leased line. to prepare for the CCENT and CCNA R&S exams. providing a path for the data. The DCE cable also does the equivalent of an Ethernet crossover cable by swapping the transmit and receive wire pairs. with no CSUs and with no leased line from the telco.Chapter 13: Implementing Point-to-Point WANs 335 – Send When Clocked – Receive When Clocked – Use Clocking to Control Router – Use Configured Speed Clock Signals CSU/ DSU Serial Cable DTE Figure 13-7 DCE DCE and DTE Roles for a CSU/DSU and a Router Serial Interface Building a WAN Link in a Lab On a practical note. without a real leased line from a telco. First. which allows the two cables to be attached directly. You can create an equivalent WAN link just by connecting two routers’ serial interfaces using one DTE cable and a slightly different DCE cable. sell a single cable that combines the two cables shown in Figure 13-8 into a single cable.indb 335 6/1/16 12:02 PM . and without CSU/DSUs. If you do. 9781587205798_BOOK. the serial cables normally used between a router and an external CSU/DSU are called DTE cables. 13 NOTE Many vendors. note that the DTE serial cable acts as a straight-through cable and does not swap the transmit and receive pair. for convenience. Search online for “Cisco serial crossover” to find examples. the serial cables in earlier Figure 13-4 are DTE cables. at the bottom of the figure. The DCE cable has a female connector. you might choose to buy some used router and switch hardware for hands-on practice. just using a cabling trick. as shown in Figure 13-8. whereas the DCE cable does swap the pairs. with the wiring details at the bottom. clock rate Command Goes Here DTE DCE Serial Cable Serial Cable Router 1 Router 2 Tx Rx Tx Tx Tx Rx Rx Rx DTE Cable Figure 13-8 DCE Cable Serial Cabling Uses a DTE Cable and a DCE Cable The figure shows the cable details at the top. That is. That completes the physical connection. when building a real WAN link with a real telco facility between sites. and the DTE cable has a male connector. This short discussion tells you enough information to create a WAN link in your home lab. In particular.

when a router sends a frame. A router serial interface can provide clocking. the router with the DCE cable installed must provide clocking. the HDLC trailer has a Frame Check Sequence (FCS) field that the receiving router can use to decide whether the frame had errors in transit. with only two routers on a link. For instance. Cisco adds another function to the ISO standard HDLC protocol by adding an extra field (a Type field) to the HDLC header. Both the Address and Control fields had important purposes in years past. Newer IOS versions will sense the presence of a DCE cable and automatically set a clock rate. creating a Cisco-specific version of HDLC. It promises to deliver bits between the devices connected to the leased line. Layer 2 Leased Lines with HDLC A leased line provides a Layer 1 service. Routers use HDLC just like any other data link protocol used by routers: to move packets to the next router. with the role of HDLC sitting at Step 2. For example. Plus. an HDLC link between two Cisco routers can forward both IPv4 and IPv6 packets because the Type field can identify which type of packet is encapsulated inside each HDLC frame. but old IOS versions require that you configure the clock rate command. the leased line itself does not define a data link layer protocol to be used on the leased line. First. However. like all the other data link protocols.indb 336 IP Packet 802. to make the link work. the HDLC Address and Control fields have little work to do. but today they are unimportant. Proprietary Cisco HDLC (Adds Type Field) Bytes 1 1 1 2 2 FC S a at D pe Ty l tro on C ss e dr Ad ag Fl Figure 13-9 Variable Cisco HDLC Framing Today. The Type field allows Cisco routers to support multiple types of network layer packets to cross the HDLC link. it is clear that the frame is sent to the only other router on the link. HDLC has only a few big functions to perform with the simple point-to-point topology of a point-to-point leased line. but it can do so only if a DCE cable is connected to the interface and by the configuration of the clock rate command. the frame header lets the receiving router know that a new frame is coming. as shown in Figure 13-9.336 CCNA Routing and Switching ICND2 200-105 Official Cert Guide Finally. so that the link will work.3 Figure 13-10 Packets 9781587205798_BOOK. HDLC provides one option for a data link protocol for a leased line. discard the frame.3 R2 2 HDLC IP Packet HDLC 3 802. LAN1 HDLC LAN2 PC1 PC2 R1 1 802.3 IP Packet 802. and if so.3 General Concept of Routers De-encapsulating and Re-encapsulating IP 6/1/16 12:02 PM . Figure 13-10 shows three familiar routing steps.

In summary. The leased line itself provides the physical means to transmit the bits. listing the conditions for which some commands are needed. Router Ethernet interfaces require no configuration related to Layers 1 and 2 for the interface to be up and working. The Layer 1 details occur by default once the cabling has been installed correctly. The HDLC frames provide the means to encapsulate the network layer packet correctly so it crosses the link between routers. and possibly the no shutdown command. The following tasks are required only when the specifically listed conditions are true: A. serial interfaces on Cisco routers need no specific Layer 1 or 2 configuration commands. router serial interfaces usually only need an ip address command. of course. encapsulates the packet into an Ethernet frame. forwarding IP traffic. and possibly enable the interface with the no shutdown command if the interface is in an “administratively down” state. of course. plus commands that are purely optional: Step 1. To send the IP packet to router R1. a leased line with HDLC creates a WAN link between two routers so that they can forward packets for the devices on the attached LANs. As on Ethernet interfaces. use the no shutdown command in interface configuration mode to enable the interface. 13 If the interface line status is administratively down. and forwards the Ethernet frame to PC2.Chapter 13: Implementing Point-to-Point WANs 337 Here is a walkthrough of the steps in the figure: 1. many optional commands exist for serial links. PC1 encapsulates the IP packet in an Ethernet frame. 6/1/16 12:02 PM . IOS defaults to use HDLC on serial interfaces. Router R2 de-encapsulates (removes) the IP packet. The following list outlines some configuration steps. For Layer 2. B. Similarly. use the no encapsulation protocol command in interface configuration mode to use the default setting of HDLC as the data link protocol. Router Ethernet interfaces. Step 2. The router only needs to configure an IP address on the interface. use the encapsulation hdlc command in interface configuration mode to enable HDLC. 3. Alternatively. in both directions. encapsulates the packet into an HDLC frame using an HDLC header and trailer. Config Checklist However. 2. Configuring HDLC Think back to router Ethernet interfaces for a moment. Router R1 de-encapsulates (removes) the IP packet.indb 337 If an encapsulation protocol interface subcommand already exists. but the router attempts to use the serial interface once the no shutdown command is configured. Use the ip address address mask command in interface configuration mode to configure the interface IP address. and forwards the HDLC frame to router R2. the cabling needs to be completed. use Ethernet as the data link protocol by default. For Layer 1. 9781587205798_BOOK. for a non-HDLC protocol. assuming both routers’ interfaces otherwise have default settings.

Step 3.0 9781587205798_BOOK. In practice.255.indb 338 6/1/16 12:02 PM .168.1.0/24 192.0 description link to R2 clock rate 2000000 ! router eigrp 1 network G0/1 DCE Figure 13-11 Typical Serial Link Between Two Routers Example 13-1 HDLC Configuration R1# show running-config ! Note . The following steps are always optional and have no impact on whether the link works and passes IP traffic: A.2.1.168. the ip address and no shutdown commands are likely the only configuration commands you would need. It also shows optional Step 3B (description).255.338 CCNA Routing and Switching ICND2 200-105 Official Cert Guide If the serial link is a back-to-back serial link in a lab (or a simulator).1 255.4. and Example 13-1 shows the matching HDLC configuration. S0/0/1 192. use the clock rate speed command in interface configuration mode to configure the clocking rate. requiring Steps 1 (ip address) and 2C (clock rate) from the preceding list. the serial link was created with a back-to-back serial link in a lab.0/24 192. In this case.2. when you configure a Cisco router with no preexisting interface configuration and install a normal production serial link with CSU/DSUs.0 network 192.1 S0/0/0 R1 192. 192.0 ! interface Serial0/0/0 ip address 192.4. Use the bandwidth speed-in-kbps command in interface configuration mode to configure the link’s documented speed so that it matches the actual clock rate of the link.1.168.1 255.168.0/24 R2 192. use the description text command in interface configuration mode to configure a description of the purpose of the interface.1.168.168. B.168. Figure 13-11 shows a sample internetwork. For documentation purposes.2. C. Use this command only on the one router with the DCE cable (per the show controllers serial number command).168.only the related lines are shown interface GigabitEthernet0/0 ip address G0/0 192.

It also lists the IP address. including the default encapsulation value (HDLC) and default bandwidth setting on a serial interface (1544.35. 19290 bytes. 0 CRC. Example 13-2 lists two commands that confirm the configuration on R1 and some other default settings. 0 overrun. rxload 1/255 Encapsulation HDLC. txload 1/255. and description. 0 no buffer Received 96 broadcasts (0 IP multicasts) 0 runts. First. The matching configuration on R2’s S0/0/1 interface simply needs an ip address command plus the default settings of encapsulation hdlc and no shutdown. DLY 20000 usec.544 Mbps). 0 collisions. 0 abort 284 packets output. clock rate 2000000 ! lines omitted for brevity R1# show interfaces s0/0/0 Serial0/0/0 is up.Chapter 13: Implementing Point-to-Point WANs 339 The configuration on R1 is relatively simple. Total output drops: 0 Queueing strategy: fifo Output queue: 0/40 (size/max) 5 minute input rate 0 bits/sec. 0 underruns 0 output errors. The show interfaces S0/0/0 command lists the various configuration settings near the top. output 00:00:00.2. line protocol is up Hardware is WIC MBRD Serial Description: link to R2 Internet address is 192. output hang never Last clearing of "show interface" counters never Input queue: 0/75/0/0 (size/max/drops/flushes). which confirms that R1 indeed has a DCE cable installed and that the clock rate has been set to 2000000 bps. 0 ignored. 0 frame.1/24 MTU 1500 bytes. meaning 1544 Kbps or 1. so R2 must be connected to a DTE cable. prefix-style mask (/24). 0 packets/sec 276 packets input. Example 13-2 Verifying the Configuration Settings on R1 R1# show controllers serial 0/0/0 Interface Serial0/0/0 Hardware is SCC DCE V. BW 1544 Kbit/sec. reliability 255/255.indb 339 DSR=up DTR=up RTS=up CTS=up 6/1/16 12:02 PM . 0 packets/sec 5 minute output rate 0 bits/sec.168. as configured in Example 13-1. 19885 bytes. 5 interface resets 0 unknown protocol drops 0 output buffer failures. loopback not set Keepalive set (10 sec) Last input 00:00:01. 0 throttles 0 input errors. 0 giants. 0 output buffers swapped out 13 7 carrier transitions DCD=up 9781587205798_BOOK. The clock rate command would not be needed on R2 because R1 has the DCE cable. it lists the output from the show controllers command for S0/0/0.

Generally speaking. PPP. and the second refers to Layer 2 status. This section ends with some configuration examples using PPP. Example 13-3 Brief Lists of Interfaces and Interface Status R1# show ip interface brief Interface IP-Address OK? Method Status Protocol GigabitEthernet0/0 192. This second major section of this chapter first discusses PPP concepts. PPP Concepts PPP provides several basic but important functions that are useful on a leased line that connects two devices: ■ Definition of a header and trailer that allows delivery of a data frame over the link ■ Support for both synchronous and asynchronous links ■ A protocol Type field in the header.1 YES manual up Serial0/0/1 unassigned YES NVRAM administratively down down Serial0/1/0 unassigned YES NVRAM administratively down down Serial0/1/1 unassigned YES NVRAM administratively down down up R1# show interfaces description Interface Status Protocol Description Gi0/0 up up Gi0/1 admin down down Se0/0/0 up up Se0/0/1 admin down down Se0/1/0 admin down down Se0/1/1 admin down down LAN at Site 1 link to R2 Leased-Line WANs with PPP Point-to-Point Protocol (PPP) plays the same role as HDLC: a data link protocol for use on serial links. However.340 CCNA Routing and Switching ICND2 200-105 Official Cert Guide Finally.1 YES manual up up GigabitEthernet0/1 unassigned YES manual administratively down down Serial0/0/0 192. allowing multiple Layer 3 protocols to pass over the same link ■ Built-in authentication tools: Password Authentication Protocol (PAP) and Challenge Handshake Authentication Protocol (CHAP) 9781587205798_BOOK. the router uses the serial interface only if it reaches an up/up interface status. For a quicker look at the interface status.indb 340 6/1/16 12:02 PM . TCP/IP. defined in the 1990s. instead use either the show ip interface brief or show interfaces description commands. In contrast. was designed with routers.2. as shown in the first line of the output of the show interfaces S0/0/0 command in Example 13-2. with many more advanced features. and other network layer protocols in mind.168. the first status word refers to Layer 1 status. including one example of a more advanced PPP feature (authentication).168.1. as listed in Example 13-3. HDLC was created for a world without routers.

the PPP standard defines a protocol field. PPP uses a series of PPP control protocols (CP). the link uses one instance of LCP plus IPCP (for IPv4). this field allowed packets from the many different Layer 3 protocols to pass over a single link. and Cisco Discovery Protocol (CDP). allowing easier integration and support of those protocols The next several pages take a closer look at the protocol field. Later. The idea of these extra protocols works a little like how Ethernet includes additional protocols like Spanning Tree Protocol (STP). When PPP was created. PPP defines the frame format in Figure 13-12. PPP authentication.Chapter 13: Implementing Point-to-Point WANs 341 ■ Control protocols for each higher-layer protocol that rides over PPP. PPP Framing Unlike the standard version of HDLC. The PPP LCP implements the control functions that work the same regardless of the Layer 3 protocol. 9781587205798_BOOK. PPP defines a set of Layer 2 control protocols that perform various link control functions. plus it defines overhead protocols like STP to help make the frame forwarding process work better. gives the LCP feature names. the section “Implementing Multilink PPP” discusses the Multilink PPP (MLPPP) feature. in more detail. and describes the features briefly. the text explains one of the features.indb 341 6/1/16 12:02 PM . each focused on the data link itself. IPv6CP (for IPv6). The protocol field identifies the type of packet inside the frame. such as IP Control Protocol (IPCP). ■ Network Control Protocols (NCP): This is a category of protocols. the protocol Type field still provides the same function. which happens to mirror the Cisco-proprietary HDLC framing that includes a protocol Type field (as shown earlier in Figure 13-9). Likewise. Each protocol performs functions specific to its related Layer 3 protocol. usually Layer 3 protocols. Figure 13-12 shows the PPP framing. IPv6. usually supporting packets for the two different versions of IP (IPv4 and IPv6). Today. For example. authentication. and the control protocols. plus it defines other protocols to help manage and control the serial link. 13 Table 13-4 summarizes the functions of LCP. For features related to any higher-layer protocols. one per network layer protocol. PPP separates these control protocols into two main categories: ■ Link Control Protocol (LCP): This one protocol has several different individual functions. Ethernet has headers and trailers to deliver frames. on a PPP link using IPv4. and CDPCP (for CDP). Following the table. PPP uses one instance of LCP per link and one NCP for each Layer 3 protocol defined on the link. PPP Bytes 1 1 1 2 2 S FC a at D pe Ty l tro on C ss e dr Ad ag Fl Figure 13-12 Variable PPP Framing PPP Control Protocols In addition to HDLC-like framing. ignoring the Layer 3 protocol sent across the link.

authentication takes two steps. WAN authentication is most often needed when dial lines are used. claiming to be legitimate by listing a secret password in clear text. configured with Barney’s name and password. Wait on Other Router Here is My Text Password I Am Barney 1 Password = Betty Fred (Authenticating) Figure 13-13 2 Ack. Barney sends the shared password in clear text. uses different messages. PPP defines two authentication protocols: PAP and CHAP. and it hides the password. With CHAP. a much more secure option. allowing rerouting over better routes Multilink support Multilink PPP Load balances traffic over multiple parallel links Authentication PAP and CHAP Exchanges names and passwords so that each device can verify the identity of the device on the other end of the link PPP Authentication In networking. which asks the other device to reply. However. but with different details. Both protocols require the exchange of messages between devices. In other words. For instance. and not some imposter. With PAP. Barney (Being Authenticated) PAP Authentication Process In the figure. and sends back an acknowledgment that Barney has passed the authentication process. CHAP. authentication gives one device a way to confirm that another device is truly the correct and approved device with which communications should occur. and disables the interface. R1 wants to authenticate R2. In that scenario. confirming that it is the correct password. Fred. allowing rerouting over a working route Error detection Link-quality Disables an interface that exceeds an error percentage monitoring (LQM) threshold. Fred. At Step 1. if R1 and R2 are supposed to be communicating over a serial link. the configuration of the authentication features remains the same whether a leased line or dial line is used. with PPP. The big difference is that the second message 9781587205798_BOOK. confirm that Barney is the real Barney—sees the password. the process works with the to-be-authenticated device starting the messages. who wants to authenticate Barney—that is. checks that configuration. R1 might want R2 to somehow prove that the device claiming to be R2 really is R2.342 CCNA Routing and Switching ICND2 200-105 Official Cert Guide Table 13-4 PPP LCP Features Function LCP Feature Description Looped link detection Magic number Detects whether the link is looped. the device doing the authentication (Fred) begins with a message called a challenge.indb 342 6/1/16 12:02 PM . as shown in Figure 13-13. authentication confirms that the other party is the authentic other party. when the link comes up. with the authentication process providing a way for R2 to prove its identity.

and the router cannot forward and receive frames on the interface. the authenticating router generates and uses a different random number. called message digest 5 (MD5). And of course. The next topic looks at how to configure and verify PPP. the same internetwork used for the HDLC example. CHAP instead uses a one-way hash algorithm. The CHAP process also uses a hash value only one time so that an attacker cannot just make a copy of the hashed value and send it at a later date. If the password is indeed the correct password. if the authentication fails. requires only one change: using the encapsulation ppp command on both ends of the link. The example includes the IP address configuration. Fred sends back a third message to confirm the successful authentication of Barney. 13 Example 13-4 shows a simple configuration using the two routers shown in Figure 13-11. As with HDLC. other items can be optionally configured. Also. as compared to HDLC. a different final message flows. with input to the algorithm being a password that never crosses the link plus a shared random number. To make that work. the next time the authentication process work occurs. Router Fred has been preconfigured with Barney’s name and password in such a way that Fred can confirm that the hashed password sent by Barney is indeed the same password that Fred lists in his configuration for Barney. the CHAP challenge (the first CHAP message) states a random number. When it fails (for instance. The challenged router runs the hash algorithm using the just-learned random number and the secret password as input.indb 343 6/1/16 12:02 PM . if the passwords do not match). But the configuration to migrate from HDLC to PPP just requires the encapsulation ppp command on both routers’ serial interfaces. The router that sent the challenge runs the same algorithm using the random number (sent across the link) and the password (as stored locally). Later. if the results match. 9781587205798_BOOK. and sends the results back to the router that sent the challenge. PAP and CHAP are a few examples of the work done by PPP’s LCP. Implementing PPP Configuring PPP. and a description of the interface. PPP leaves the interface in an up/down state. the interface must be enabled (no shutdown). but the IP addresses do not have to be configured for PPP to work.Chapter 13: Implementing Point-to-Point WANs 343 in the flow (as shown in Figure 13-14) hides the authentication password by instead sending a hashed version of the password. These can be read easily if someone places a tracing tool in the circuit. Ask Other Router React to Challenge 1 Challenge! I Am #$%#$@ Fred (Authenticating) Figure 13-14 3 Accepted 2 Barney (Being Authenticated) CHAP Authentication Process Both Figures 13-13 and 13-14 show authentication flows when authentication works. such as the interface bandwidth. PAP flows are much less secure than CHAP because PAP sends the hostname and password in clear text in the message. the passwords must match.

LCP Open Open: IPCP. authorization. The output looks just like it does for HDLC up until the first highlighted line in the example. 9781587205798_BOOK. the password could be configured on an external authentication. Define the usernames and passwords used by the two routers: A.344 CCNA Routing and Switching ICND2 200-105 Official Cert Guide Basic PPP Configuration Example 13-4 ! The example starts with router R1 interface Serial0/0/0 ip address 192. Step 2. Finally. CDPCP and IPCP. to set the local router’s name to use when authenticating. DLY 20000 usec.0 encapsulation ppp clockrate 2000000 ! Next. Use the encapsulation ppp command in interface configuration mode.0 encapsulation ppp The one show command that lists PPP details is the show interfaces command. 6/1/16 12:02 PM . have also successfully been enabled—all good indications that PPP is working properly.1/24 MTU 1500 bytes.) To configure PPP along with CHAP on an interface that has all default configuration on the serial interfaces of both routers. on the serial interfaces on both routers.indb 344 Use the hostname name command in global configuration mode on each router. CDPCP. reliability 255/255. txload 1/255. loopback not set ! Lines omitted for brevity Implementing PPP CHAP The simplest version of CHAP configuration requires only a few commands.2. the configuration on router R2 interface Serial0/0/1 ip address 192. to enable PPP on the interfaces. as noted with the “LCP Open” phrase. follow these steps: Config Checklist Step 1.255.2 255.1 255.255. These lines also confirm that LCP has completed its work successfully.168. and NCP Status with show interfaces R1# show interfaces serial 0/0/0 Serial0/0/0 is up. LCP.255.168. with an example from R1 listed in Example 13-5. Example 13-5 Finding PPP. line protocol is up Hardware is WIC MBRD Serial Description: link to R2 Internet address is 192. The configuration uses a password configured on each router. The two highlighted lines confirm the configuration (“Encapsulation PPP”).168. and accounting [AAA] server outside the router. the output lists the fact that two CPs.255. (As an alternative.2.2. rxload 1/255 Encapsulation PPP. BW 1544 Kbit/sec.

LCP Open 13 Open: IPCP.Chapter 13: Implementing Point-to-Point WANs 345 B.2.2. DLY 20000 usec. rxload 1/255 Encapsulation PPP. line protocol is up Hardware is WIC MBRD Serial Description: link to R2 Internet address is 192. hostname R1 hostname R2 username R2 password mypass username R1 password mypass interface serial 0/0/0 ip address 192. with CHAP enabled per Figure 13-15.255. the show interfaces command does not list “LCP Open” as shown in this example.1/24 MTU 1500 bytes. To check that status. (The name in the username command should match the name in the neighboring router’s hostname command. Step 3. reliability 255/255.2. txload 1/255. with CHAP working. Figure 13-15 shows the configuration on both R1 and R2 to both enable PPP and add CHAP to the link.indb 345 6/1/16 12:02 PM . BW 1544 Kbit/sec.) Use the ppp authentication chap command in interface configuration mode on each router to enable CHAP on each interface. and the matching password (case-sensitive). use the usual show interfaces [type number] command or show interfaces status command.2 255.255. CDPCP. the protocol status of the interface falls to a down state.1 255.168. First.255.168.255. if CHAP authentication is enabled but CHAP authentication fails. if CHAP is enabled but CHAP authentication fails. However. It also shows that the password defined in each username command must be the same (mypass in this case).168. Example 13-6 lists the output of the show interfaces serial0/0/0 command from R1. Example 13-6 Confirming CHAP Authentication with show interfaces R1# show interfaces serial 0/0/0 Serial0/0/0 is up. Additionally.0 encapsulation ppp ppp authentication chap Router R2 CHAP Configuration You can confirm that CHAP authentication has succeeded in a couple of ways. Use the username name password password command in global configuration mode on each router. loopback not set Keepalive set (10 sec) ! Lines omitted for brevity 9781587205798_BOOK. note that this command does not tell us whether authentication has been configured or not. to define the name (case-sensitive) used by the neighboring router. The figure shows how the name in the hostname command on one router must match the username command on the other router.0 encapsulation ppp ppp authentication chap Router R1 Figure 13-15 interface serial 0/0/1 ip address 192.

with CHAP authentication. Once sent. worked. The highlighted header in the example is the column where this command lists various PPP protocols and their status. The highlighted parts of this command in the example confirm that Serial0/0/0 uses PPP. Then. and compares those values with its various username password global commands. with a plus sign (+) meaning that the listed protocol is OPEN. 9781587205798_BOOK.-------. again assuming authentication is configured. if configured.--------------------. The line protocol status being up confirms that authentication. A router defines the username/password pair it will send using the ppp pap sent-username command. Figure 13-16 shows a completed configuration for two routers (R1 and R2). the LCP status of Open also confirms that authentication worked.346 CCNA Routing and Switching ICND2 200-105 Official Cert Guide R1# show ppp all Interface/ID OPEN+ Nego* Fail- Stage Peer Address Peer Name -----------.2.0 encapsulation ppp ppp authentication pap ppp pap sent-username R1 password pass1 username R2 password pass2 R1 Global Commands Figure 13-16 R2 Global Commands username R1 password pass1 interface serial 0/0/1 ip address 192. In particular. PAP uses the similar authentication ppp pap command instead of the authentication ppp chap command. with emphasis on matching the ppp pap sent-username command on one router with the username password commands on the other router. Implementing PPP PAP PAP configuration differs from CHAP configuration in a couple of ways. nothing in the show interfaces command output tells us whether or not CHAP or PAP has been configured. configured as an interface subcommand.168.168.1 255. PAP configures the sent username/password pair much differently than CHAP.255.-------------------Se0/0/0 LCP+ CHAP+ IPCP+ CDP> LocalT 192. This command lists a single line per PPP connection in the router.indb 346 6/1/16 12:02 PM .255.0 encapsulation ppp ppp authentication pap ppp pap sent-username R2 password pass2 R2 Interface Commands PAP Configuration Example 13-7 now shows two commands used to verify PAP operation.) As with CHAP. First.168. and a minus sign (–) meaning that the protocol has failed. R1 Interface Commands interface serial 0/0/0 ip address 192. and that CHAP authentication worked (as proved by the OPEN status of the CHAP protocol).--------------.2 R2 The more obvious way to confirm that CHAP works is to use the show ppp all command. as shown at the end of Example 13-6. note that the show interfaces command tells us nothing more and nothing less as compared to using CHAP authentication. (However.255.2. the other router receives that username/password pair.2 255.2.255.

line protocol is up Hardware is WIC MBRD Serial Description: link to R2 Internet address is 192.--------------. it then tries CHAP.168. and in this case the protocol is OPEN.2. rxload 1/255 Encapsulation PPP.1/24 MTU 1500 bytes. LCP Open Open: IPCP. you end up with a design that looks like the design in Figure 13-17. DLY 20000 usec. BW 1544 Kbit/sec. or the ppp authentication chap pap command to try CHAP first. so if one link fails.168.-------------------Se0/0/0 LCP+ PAP+ IPCP+ CDPC> LocalT 192. or when using no authentication at all. with multiple serial links between two routers.168.Chapter 13: Implementing Point-to-Point WANs 347 However. which identifies PAP as configured on interface Serial0/0/0.3. just as is the case when using CHAP. reliability 255/255. rather than a single serial link.-------.1 S0/0/0 192.2 ciscouser2 Finally. loopback not set Keepalive set (10 sec) ! Lines omitted for brevity R1# show ppp all Interface/ID OPEN+ Nego* Fail- Stage Peer Address Peer Name -----------.5 Mbps each) rather than move up to the next faster type of line. and add the ppp authentication pap chap command to try PAP first. S0/0/1 13 R1 R2 S0/1/1 192. note that you can configure the interface to try using the PAP process first.168.0/24 192.--------------------.168. txload 1/255. using a fractional T3 service. meaning that authentication worked. if it is configured. CDPCP. which authentication protocol is used.2. 192.2 Multiple Parallel Serial Links Between Routers 6/1/16 12:02 PM . You can configure to try PAP first or CHAP first. Implementing Multilink PPP Network designers sometimes use multiple parallel serial links between two routers. Just configure the commands to support both.168. Configuring and Verifying PAP Authentication Example 13-7 R1# show interfaces serial 0/0/0 Serial0/0/0 is up. a T3 line. Whatever the reasons.3.168.1 Figure 13-17 9781587205798_BOOK. at least the others are working. but if the other side does not support PAP.9. The better confirmation comes from the show ppp all command at the bottom of the example.indb 347 S0/1/0 192. That motivation may be to improve availability. this command does not confirm whether authentication has been configured or. The motivation may be simple economics—it may be cheaper to install two or three parallel T1 lines (at about 1.0/24 192.2.

with two links. routers would have one subnet between routers.168. 192. Figure 13-18 shows the concept of having multiple equal-metric routes.0/24 1 Two EIGRP Neighbor Relationships R1 R2 2 Route to However.0/24 .9. with routing protocol neighbor relationships formed over each link.168.168. one routing protocol neighbor relationship. the interior routing protocol would run over each of the parallel links. R1 has one route for network 192. IOS can be configured to balance on a packet-by-packet basis. It shows the same design as Figure 13-17. One Per Parallel Serial Link The Layer 3 routing logic in Cisco IOS will then balance packets across the multiple links using the routes as shown in the figure. Figure 13-19 shows these main ideas for the same physical topology shown in Figure 13-18.168.168. with all packets going to destination address 192. and multiple equal-metric routes learned for each remote subnet.9.0/24 over the top link. Only Route to 192.0/24 192. with multiple routing protocol neighbor relationships. IOS balances on a destination-bydestination address basis—for instance.2 being routed over the lower link.9. one over each link. PPP offers a feature that simplifies the Layer 3 operations in topologies that use multiple parallel PPP links. Multilink PPP Concepts Multilink PPP (MLPPP) is a PPP feature useful when using multiple parallel serial links between two devices.2 Multilink 1 EIGRP Neighbors R2 Layer 3 Concept Created by Multilink Interface 6/1/16 12:02 PM . It provides two important features.9.168.1. and works well in many cases. Using the Layer 3 features discussed in the last page or so works. all packets to 192. and one over the bottom link.5. in Figure 13-18. which has multiple physical links. First.1 might flow over the top link.9.168.1 Route to 192.348 CCNA Routing and Switching ICND2 200-105 Official Cert Guide If the network engineer configures the parallel serial links as discussed so far in this chapter. Instead of multiple subnets between routers. each router would learn multiple routes to every remote destination subnet—one such route for each parallel link.168. By default.indb 348 192.5. and one route per destination subnet. If using EIGRP. To make that happen. with a feature called Multilink PPP (MLPPP).1 Multilink 1 R1 Figure 13-19 9781587205798_BOOK. it reduces the Layer 3 complexity by making the multiple serial interfaces on each router look like a single interface from a Layer 3 perspective.168.0/24 192. one for each of the parallel serial links.0/24 192. R1 would have two EIGRP neighbor relationships with R2.0/24 .2 Figure 13-18 Two IP Routes for One Network. each link has IP addresses and can be used to forward IP packets.168. As a result.

Cisco routers will balance the bytes sent equally across the active links in the multilink bundle.Chapter 13: Implementing Point-to-Point WANs 349 MLPPP makes the multiple physical links work like a single link by using a virtual interface called a multilink interface.indb 349 13 6/1/16 12:02 PM . 9781587205798_BOOK. 2 3 PPP IP 4 1 5 IP IP R1 R2 3 Figure 13-20 PPP IP Layer 2 Fragmentation to Balance Traffic over Multiple Links MLPPP’s load-balancing process allows for some small variations in the sizes of the fragments. with an encapsulated IP packet arriving at Step 1. Steps 1 and 2 show normal routing. and routing protocol) under the multilink interfaces (and not on the serial interfaces). For instance. MLPPP fragments the packet into pieces (called fragments). like clock rate (Layer 1) and ppp authentication (Layer 2). When IOS internally routes a packet out a multilink interface. if three links are active. Configure the serial interfaces with all Layer 1 and 2 commands. the router forwards about one-third of the byte volume of traffic. but for the most part. connecting the Layer 2 logic that works with the multiple serial links with the Layer 3 logic that works on the single multilink interface. Interestingly. IPv6. The Layer 3 configuration (like IPv4 and IPv6 addresses and routing protocol interface subcommands) is added to the multilink interface. Step 3. Configure matching multilink interfaces on the two routers. Configure some PPP commands on both the multilink and serial interfaces. and load balancing the frame. However. MLPPP load-balancing logic takes over. The receiving router reassembles the fragments back into the original packet (Step 4). to both enable MLPPP and associate the multilink interface with the serial interfaces. Configuring MLPPP Implementing MLPPP requires a longer configuration than most features discussed in this book. with normal IP routing shown at Step 5. Then the configuration associates the physical serial interfaces with the multilink interface. with a PPP header/ trailer around each. So first. Step 2. encapsulating the packet into a new data link frame. one per active link. with the packet exiting a multilink interface. a router’s Layer 3 forwarding logic forwards each packet out the multilink interface. with a few extra header bytes to manage the fragmentation process. as shown with the process in Figure 13-20. In addition to simplifying Layer 3 details as just described. MLPPP balances the frames sent at Layer 2 over the multiple links. configuring the interface subcommands for all Layer 3 features (IPv4. MLPPP load balances the data link frame by fragmenting the frame into multiple smaller frames. to set the context a bit. think about these main three configuration requirements for MLPPP: Step 1. With MLPPP. and the router making the usual routing decision at Step 2.

NOTE Figure 13-21 shows only one serial interface. but each serial interface in the multilink group would need the same configuration. Figure 13-21 shows the configuration for only one of the two serial interfaces.5.255. focus on the six configuration commands noted with white highlight boxes in Figure 13-21 as pointed to with arrows.1 255. In short. The network engineer chooses the interface number. and they must all again refer to that same number (1 in this example). Note that for space.255.2 255. As a result. and the serial interfaces do not.350 CCNA Routing and Switching ICND2 200-105 Official Cert Guide Figure 13-21 shows all the specific MLPPP commands in a working example. Finally. note that both the multilink and serial interfaces have two additional commands: encapsulation ppp (which enables PPP). the routing and routing protocol logic will work with the multilink interface. Any number in range could be used. The interface multilink 1 command on each router creates the multilink interface on that router.indb 350 6/1/16 12:02 PM . Additionally. or the link will not work. the multilink interfaces and the physical serial interfaces must all have both a ppp multilink group 1 command.0 ppp multilink group 1 interface multilink 1 encapsulation ppp ppp multilink ip address 192. Note that the configuration shows IPv4 addresses configured on the multilink interfaces. R1 Multilink (Layer 3) Interface R2 Multilink (Layer 3) Interface interface multilink 1 encapsulation ppp ppp multilink ip address 192. and ppp multilink (which adds multilink support). the multilink interface has the Layer 3 configuration. but the number must be the same on both routers. The example is based on the design in Figures 13-19 and 13-20.255. but no IPv4 address at all on the serial interface.168.168. First.5.255. but the number must match with the commands highlighted in the figure. 9781587205798_BOOK. but all serial interfaces would have the same subcommands when used for MLPPP.0 ppp multilink group 1 interface Serial0/0/0 encapsulation ppp ppp multilink no ip address ppp multilink group 1 ! Authentication goes here interface Serial0/0/1 encapsulation ppp ppp multilink no ip address ppp multilink group 1 ! Authentication goes here R1 Layer 2 Interfaces R2 Layer 2 Interfaces Must Be Same Number Figure 13-21 MLPPP Configuration Now look at the ip address commands.

because they do not have IP addresses and the router’s routing logic works with the multilink interface instead.168. Similarly.168. Multilink1 C 192. 2 subnets.1.Chapter 13: Implementing Point-to-Point WANs 351 Verifying MLPPP To verify that an MLPPP interface is working.5. Multilink1 R1# show ip eigrp interfaces EIGRP-IPv4 Interfaces for AS(1) Xmit Queue PeerQ Mean Pacing Time Multicast Pending Peers Un/Reliable Un/Reliable SRTT Un/Reliable Flow Timer Routes Mu1 1 0/0 0/0 1 0/8 50 0 Gi0/0 1 0/0 0/0 1 0/0 50 0 Interface R1# show ip interface brief Interface IP-Address OK? Method Status Protocol Embedded-Service-Engine0/0 unassigned YES NVRAM administratively down down GigabitEthernet0/0 192.9.0/24 is variably subnetted. it helps to think about the Layer 3 features separately from Layer 1 and Layer 2 details. However. 2 masks C 192.168. For Layer 3.168.1. all the usual IPv4.5.0/24 is directly connected.5. 3 subnets. GigabitEthernet0/0 L 192.168.1 YES manual up up Working from the top of the example to the bottom.1/32 is directly connected. GigabitEthernet0/0 192.168.0/24 is directly connected.5. the show ip eigrp interfaces 9781587205798_BOOK. IPv6.1/32 is directly connected. You can also just ping the IP address on the other end of the multilink to test the link.5. the two serial interfaces are not listed at all. 2 masks C 192. Example 13-8 shows a few commands to confirm the current working state of the MLPPP link.1.168.168.indb 351 13 6/1/16 12:02 PM .168. 16:02:07. note that the IPv4 routing table lists interface multilink 1 as the outgoing interface in a variety of routes.2/32 is directly connected. and routing protocol commands will now list the multilink interface rather than the physical serial interfaces. Example 13-8 Verifying Layer 3 Operations with an MLPPP Multilink Interface R1# show ip route ! Legend omitted for brevity 192.0/24 is variably subnetted.1 YES manual up up GigabitEthernet0/1 unassigned YES manual up up Serial0/0/0 unassigned YES manual up up Serial0/0/1 unassigned YES manual administratively down down Serial0/1/0 unassigned YES NVRAM administratively down down Serial0/1/1 unassigned YES NVRAM up up Multilink1 192.2.168. taken from the working configuration in Figure 13-21. Multilink1 L [90/1343488] via 192.1. Multilink1 D 192.

multilink Open Open: IPCP. 0 inactive (max 255.352 CCNA Routing and Switching ICND2 200-105 Official Cert Guide command lists interfaces on which EIGRP is enabled. LCP Open. reliability 255/255. 96 reordered 0/0 discarded fragments/bytes. that working state implies that at least one of the physical links in the MLPPP group is also working— that is. since 16:23:16 No inactive multilink interfaces First.indb 352 6/1/16 12:02 PM . IOS believes the multilink interface is working. 0x654D5 sent sequence Member links: 2 active. and not listing either of the two serial interfaces in the MLPPP bundle. listing Mu1 (Multilink 1).1/24 MTU 1500 bytes. load 1/255 Receive buffer limit 24000 bytes. In particular. rxload 1/255 Encapsulation PPP. line protocol is up Hardware is multilink group interface Internet address is 192. since 16:50:33 Se0/0/0. DLY 20000 usec.5. as noted with the “unassigned” text under the IP-Address column. some of the physical links can fail. min not set) Se0/1/1. the output shows the traditional line and 9781587205798_BOOK. frag timeout 1000 ms 0/0 fragments/bytes in reassembly list 0 lost fragments. 0 lost received 0x654D7 received sequence. You can always directly verify the serial interfaces in the multilink group with the same commands discussed earlier in the chapter (show controllers.168. total bandwidth 3088. but the output confirms that no IP address has been configured on the serial interfaces. loopback not set Keepalive set (10 sec) ! lines omitted for brevity R1# show ppp multilink Multilink1 Bundle name: R2 Remote Username: R2 Remote Endpoint Discriminator: [1] R2 Local Username: R1 Local Endpoint Discriminator: [1] R1 Bundle up for 16:50:33. note that the show ip interface brief command does list both the serial interfaces and the multilink interface. Example 13-9 Verifying Operational Details of an MLPPP Group R1# show interfaces multilink 1 Multilink1 is up. CDPCP. BW 3088 Kbit/sec. Each multilink interface has a line and protocol status like any other interface. Additionally. and if that status is up/up. show interfaces). the two commands in Example 13-9 give some insight into the specifics of MLPPP operation. txload 1/255. Finally. notice that the show interfaces multilink 1 command lists many familiar details and some mentions about multilink. and the multilink stays up. By default.

meaning that the interface is working.168. interfaces S0/0/0 and S0/1/1 are active. as discussed in Chapter 11.2. this section does not attempt to repeat the IP troubleshooting coverage in Part II of this book. From one router. also verify that any routing protocols are exchanging routes over the link. which prevents the routers from routing packets over the serial link. Step 3. the problem could be related to functions at Layer 1. Troubleshooting Serial Links This final major section discusses how to isolate and find the root cause of problems related to topics covered earlier in this chapter. both in an up state.” 13 NOTE The interface status codes can be found using the show interfaces. A simple ping command can determine whether a serial link can or cannot forward IP packets. On the sixth line. Finally. and show interfaces description commands. on R1. or 3. “Troubleshooting IPv4 Routing Protocols. If the ping fails. The best way to isolate which layer is the most likely cause is to examine the interface status codes described in Table 13-5.Chapter 13: Implementing Point-to-Point WANs 353 protocol status. The timer to the side shows that both have been active a little over 16 hours. but it does point out some of the possible symptoms on a serial link when a Layer 3 subnet mismatch occurs on opposite ends of a serial link. as well as which ones are active. but that the MLPPP configuration includes both of these links in multilink group 1. Seeing these two interfaces in the list confirms not only that the physical interfaces are working. Table 13-5 Interface Status Codes and Typical Meanings When a Ping Does Not Work Line Status Protocol Status Likely General Reason/Layer Administratively down Down Interface shutdown Down Down Layer 1 Up Down Layer 2 Up Up Layer 3 The serial link verification and troubleshooting process should begin with a simple threestep process: Step 1. the figure used for both the HDLC and PPP configuration examples—proves that the link either works or does not. In this case. Step 2. confirming that MLPPP is in effect. show ip interface brief. the output mentioned a working multilink state of “Open” in the section about PPP control protocols. the output of the show ppp multilink command identifies the links configured in each multilink bundle.2 command on R1 in Figure 13-11. 2. If the ping does not work. A ping of the other router’s serial IP address—for example. Also. ping the other router’s serial IP address.indb 353 6/1/16 12:02 PM . 9781587205798_BOOK. examine the interface status on both routers and investigate problems related to the likely problem areas listed in Table 13-5. If the ping works. a working ping 192. as highlighted at the bottom of the example.

play a key role in isolating the root cause of problems on serial links. Unplugged Cable Interface Shutdown Misconfigured or Broken CSU TELCO Facilities Problem R1 S0/0/0 CSU CSU S0/0/1 R2 Line: Down Protocol: Down Figure 13-22 Problems That Result in a Down/Down State on Router R2 Troubleshooting Layer 2 Problems Data link layer problems on serial links usually result in at least one of the routers having a serial interface status of up/down. or interface state. Table 13-6 lists some of these types of problems. Table 13-6 Likely Reasons for Data Link Problems on Serial Links Line Status Protocol Status ends1 Likely Reason Up Down on both Up Down on one end. the other router sits in a down/down state (line status down. Bad Cable. The solution is to just configure a no shutdown interface configuration command on the interface. the state may flap from up/up. up on the other Keepalive disabled on the end in an up state when using HDLC Up Down on both ends PAP/CHAP authentication failure Mismatched encapsulation commands 1 In this case. a serial link fails when just one of the two routers has administratively disabled its serial interface with the shutdown interface subcommand. and so on. the center and left side of the figure show common root causes that then result in R2’s serial interface being in a down/down state.indb 354 6/1/16 12:02 PM . so it is important to examine the status on both ends of the link to help determine the problem. both ends in a down/down state—usually points to some Layer 1 problem. In the figure. In fact. the line status (the first status code) is up. line protocol status down). based on the combinations of interface status codes listed in Table 13-5. assuming the second router’s interface is not also shut down. R2’s serial interface has no problems at all. 9781587205798_BOOK. For example. the status on both ends of the link may differ. When one router shuts down its serial interface. Figure 13-22 summarizes the most common causes of this state.354 CCNA Routing and Switching ICND2 200-105 Official Cert Guide The rest of this section explores the specific items to be examined when the ping fails. to up/down. while the router keeps trying to make the encapsulation work. A serial interface with a down line status on both ends of the serial link—that is. Troubleshooting Layer 1 Problems The interface status codes. In other words. to up/up. while the second status (the line protocol status) is down.

1 S0/0/0 Line: Up Protocol: Up Figure 13-23 192. because keepalives are enabled. The solution is simple: Reconfigure one of the two routers to match the other router’s encapsulation command. The keepalive process happens in both directions as well—R1 sends keepalives with R2 expecting to receive them. R2 believes R1 has failed. Note that this keepalive mismatch mistake only breaks HDLC links. ■ R2 still expects to receive keepalive messages. and R2 expects to receive those keepalive messages every 10 seconds.” meaning that keepalives are enabled with a 10-second interval. the router can bring down the interface. That combination is a mistake. For instance. allowing the routing protocol to converge to use other routes it they exist. plus remembering that HDLC is the default serial encapsulation. and R2 changes the link to an up/down state. Once a router believes the link no longer works. The show interfaces command lists the encapsulation type on about the seventh line of the output.2. 9781587205798_BOOK.168. can confirm whether the encapsulations are mismatched. the PPP keepalive feature prevents the problem. R1 sends a keepalive message every 10 seconds.Chapter 13: Implementing Point-to-Point WANs 355 The first of these problems—a mismatch between the configured data link protocols—is easy to identify and fix. and R2 sends keepalives with R1 expecting to receive them. and should not be used. In the scenario shown in Figure 13-23. Keepalive Failure The router keepalive feature helps a router notice when a link is no longer functioning. Alternatively. The examples in this chapter list several examples of the show interfaces command that happen to list the text “Keepalive set (10 second). Figure 13-23 shows one such example with HDLC and with R1 mistakenly disabling keepalives. interface serial 0/0/1 encapsulation hdlc interface serial 0/0/0 encapsulation hdlc no keepalive R1 192.168.2 S0/0/1 R2 Line: Up Protocol: Down Results when Using HDLC with a Keepalive Mismatch Note that the router interface that disables keepalives remains in an up/up state. so using this command on both routers can quickly identify the problem. on a serial link between R1 and R2. because keepalives are disabled. A keepalive mismatch occurs when one router has keepalives enabled and one router does not. R2’s interface fails because ■ R1 does not send keepalive messages. R1 would list the text “Keepalive not set” in this case. a quick look at the configuration.2.indb 355 13 6/1/16 12:02 PM . The next two sections take a closer look at each. You can verify the keepalive setting by looking at the configuration or by using the show interfaces command. defaulting to 10 seconds. The keepalive function on an interface causes routers to send keepalive messages to each other every keepalive interval. If R2 fails to receive the keepalive messages for a set number of consecutive keepalive intervals (usually three or five intervals). The other two root causes require a little more discussion to understand the issue and determine if they are the real root cause.

and that they have enabled CHAP. 3. By doing so. you can use the show interfaces and show ppp all commands to look further into the status of the PPP authentication process. shut down the link. as follows: 1. meaning that this local router. In this case. The example extracts the three related debug messages from what would be a few dozen debug messages. you will see debug messages that match that three-way exchange. If you enable the debug. R1. Note that this example was built by changing the username command to have an incorrect password. telling R2 that the authentication process failed. Example 13-10 Debug Messages on Router R1 Confirming the Failure of CHAP R1# debug ppp authentication PPP authentication debugging is on ! Lines omitted for brevity *Nov 18 23:45:48. a failure in the PAP/CHAP authentication process results in both router interfaces failing to an up and down state. Note the “from R1” at the end of the debug message. which may help you decide what specifically needs to be fixed. The “I” refers to input. It looks more like R1 has rejected the hashed password supplied by R2.820: Se0/0/0 CHAP: O FAILURE id 1 len 25 msg is "Authentication failed" While using a debug command may tell us something about the problem. The “O FAILURE” refers to R1 sending out a Failure message. However. stating who the message is from. the output highlights the important parts of the process as seen back in Figure 13-14.820: Se0/0/0 CHAP: O CHALLENGE id 1 len 23 from "R1" *Nov 18 23:45:48.indb 356 6/1/16 12:02 PM . The “O” refers to output. Note the “from R2” at the end of the line. as shown back in Figure 13-14. CHAP uses a three-message exchange. and bring it back up. Another deeper method to troubleshoot PPP authentication problems uses the debug ppp authentication command. 9781587205798_BOOK. As shown in Examples 13-6 and 13-7. If authentication fails. you see a failure message at the point at which the process fails. The network connects R1’s S0/0/0 to router R2. it does not always point to the specific command that is misconfigured. the fact that both routers send at least one CHAP message implies that both router interfaces can send frames. Example 13-10 shows the three related debug messages when a link comes up. with a set of messages flowing for authentication in each direction by default. 2. R1. has input (received) a Response message. ruling out or ruling in PPP authentication as the root cause. meaning that this local router.356 CCNA Routing and Switching ICND2 200-105 Official Cert Guide PAP and CHAP Authentication Failure As mentioned earlier. you can isolate and discover the root cause of why the interface is in an up/down state. has output (sent) a Challenge message. so you would have to look for these. so that the CHAP process worked but the authentication was rejected.820: Se0/0/0 CHAP: I RESPONSE id 1 len 23 from "R2" *Nov 18 23:45:48.

Then. Finding and fixing a mismatched subnet problem with HDLC links is relatively simple. 2 subnets. and R2’s was changed to 192.0/24 is directly connected. In some cases. representing a single host. the ping to the other router’s IP address actually works.1.2 9781587205798_BOOK. Example 13-11 shows the working PPP link with addresses in different subnets.0/32 is subnetted. First. NOTE A route with a /32 prefix. Serial0/0/0 13 R1# ping 192.indb 357 6/1/16 12:02 PM .1/32 is directly connected.168.168. GigabitEthernet0/0 192.2 (instead of 192. Even with Mismatched Subnets R1# show ip route ! Legend omitted for brevity 192. Interestingly. Example 13-11 PPP Allowing a Ping over a Serial Link.168. However. both routers’ interfaces are in an up and up state. If both interfaces have a status of up/up. Serial0/0/0 192. 2 masks C L 192. GigabitEthernet0/0 192. This short section examines the symptoms. the IP address on the serial link.2. the ping may work but the routing protocols might not be able to exchange routes.168. PPP makes the ping work with the mismatched subnet by adding a host route.168. the two routers would have connected routes to different subnets. However.3. 2 masks C L 192. 1 subnets C 192. so it is still a good idea to follow the rules and put both serial interface IP addresses in the same subnet. a ping to the IP address on the other end of the link will fail because the routers do not have a matching route. consider an example with a working HDLC link with the IP addresses shown earlier in Figure 13-23.1. for the IP address of the other router.168.168.0/24 is directly connected.0/24 is variably subnetted. 2 subnets.1. For PPP links with the same IP address/mask misconfiguration. still with a mask of /24. if the IP addresses configured on the serial interfaces on the two routers are in different subnets. if R1’s serial IP address remained 192.0/24 is variably subnetted. consider an HDLC link on which the physical and data link details are working fine.168. with a /32 prefix length. the serial link can be in an up and up state but the ping can still fail because of Layer 3 misconfiguration. In this case. They would not have a route matching the opposite router’s serial IP address. For example. the problem is likely this mismatched IP subnet. Serial0/0/0 192. the IP subnet mismatch still prevents EIGRP and OSPF neighbor relationships from forming.2).Chapter 13: Implementing Point-to-Point WANs 357 Troubleshooting Layer 3 Problems This chapter suggests that the best starting place to troubleshoot serial links is to ping the IP address of the router on the other end of the link—specifically.1.2 is directly connected. You can find the problem by doing the usual first step of pinging the IP address on the other end of the link and failing.1/32 is directly connected. is called a host route. which differ slightly depending on whether HDLC or PPP is used and the root cause.

2. specifically for R2’s new serial IP address (192. DVD. This extra host route allows the ping to the other side of the serial link to work in spite of the addresses on each end being in different subnets. timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5). DVD/website Repeat DIKTA questions Book. (R2 will have a similar route for 192.1/32. Review this chapter’s material using either the tools in the book. DVD/website Review key terms Book.168. Table 13-7 summarizes the behavior on HDLC and PPP links when the IP addresses on each end do not reside in the same subnet but no other problems exist.indb 358 6/1/16 12:02 PM .168. 100-byte ICMP Echos to 192.1/24). Sending 5. Refer to the “Your Study Plan” element for more details. R1 thinks this subnet is the subnet connected to S0/0/0 because of R1’s configured IP address (192. or interactive tools for the same material found on the book’s companion website. for network 192.168. R1’s serial IP address. To better track your study progress. Table 13-8 Chapter Review Tracking Review Element Review Date(s) Resource Used Review key topics Book. PCPT Do labs Blog Review memory tables Book.2. round-trip min/avg/max = 1/2/4 ms The first highlighted line in the example shows the normal connected route on the serial link.358 CCNA Routing and Switching ICND2 200-105 Official Cert Guide Type escape sequence to abort. even though the other router’s address is in a different subnet.168.2. The second highlighted line shows the host route created by PPP.0/24. DVD/website Review command tables Book 9781587205798_BOOK.168. record when you completed these activities in the second column.3. DVD/website Review config checklists Book.) So.2. Table 13-8 outlines the key review elements and where you can find them. Table 13-7 Summary of Symptoms for Mismatched Subnets on Serial Links Symptoms When IP Addresses on a Serial Link Are in Different Subnets HDLC PPP Does a ping of the other router’s serial IP address work? No Yes Can routing protocols exchange routes over the link? No No Chapter Review One key to doing well on the exams is to perform repetitive spaced review sessions.3. both routers have a route to allow them to forward packets to the IP address on the other end of the link.2).

and try to recall the command without looking. CSU/DSU. sets the clock speed in bps bandwidth speed-kbps Interface subcommand that sets the router’s opinion of the link speed. and try to recall what the command does. PAP. covering the right column. serial link. DTE. serial cable. cover the left column in a table. IP Control Protocol.Chapter 13: Implementing Point-to-Point WANs 359 Review All the Key Topics Table 13-9 Key Topics for Chapter 13 Key Topic Element Description Page Number Table 13-3 Speeds for WAN links per the T-carrier system 334 Figure 13-7 Role of the CSU/DSU and the router as DCE and DTE 335 List PPP features 340 List Comparison of PPP LCP and NCP 341 Figure 13-13 Example of messages sent by PAP 342 Figure 13-14 Example of messages sent by CHAP 343 Figure 13-16 Sample PAP configuration 346 List MLPPP major configuration concepts 349 Figure 13-21 Sample MLPPP configuration 350 Key Terms You Should Know leased line. T1. customer premises equipment. DCE. keepalive. read the right column. DS0. WAN link.indb 359 13 6/1/16 12:02 PM . but has no effect on the actual speed description text Interface subcommand that can set a text description of the interface ppp authentication {pap | chap} Interface subcommand that enables only PAP or only CHAP authentication username name password secret Global command that sets the password that this router expects to use when authenticating the router with the listed hostname ppp pap sent-username name password secret Interface subcommand that defines the username/password pair sent over this link when using PAP authentication 9781587205798_BOOK. Link Control Protocol. in kilobits per second. HDLC. when used on an interface with a DCE cable. Then repeat the exercise. CHAP. T3. DS1. Multilink PPP Command References Tables 13-10 and 13-11 list configuration and verification commands used in this chapter. Table 13-10 Chapter 13 Configuration Command Reference Command Description encapsulation {hdlc | ppp} Interface subcommand that defines the serial data-link protocol [no] shutdown Administratively disables (shutdown) or enables (no shutdown) the interface in whose mode the command is issued clock rate speed Serial interface subcommand that. PPP. As an easy review exercise. telco.

whether it is a DTE or DCE cable show ppp multilink Lists detailed status information about each of the PPP multilink groups configured on the router show ppp all Lists one line of status information per PPP link on the router. including the encapsulation type show interfaces [type number] description Lists a single line per interface (or if the interface is included. and if so. with IP address and interface status show controllers serial number Lists whether a cable is connected to the interface. just one line of output total) that lists the interface status and description show ip interface brief Lists one line of output per interface. including the status for each control protocol debug ppp authentication Generates messages for each step in the PAP or CHAP authentication process debug ppp negotiation Generates debug messages for the LCP and NCP negotiation messages sent between the devices 9781587205798_BOOK.360 CCNA Routing and Switching ICND2 200-105 Official Cert Guide Command Description interface multilink number Creates a multilink interface and moves the user to interface configuration mode on that interface ppp multilink Interface subcommand that enables MLPPP features ppp multilink group number Interface subcommand that associates the interface with a particular multilink interface and multilink group Table 13-11 Chapter 13 EXEC Command Reference Command Description show interfaces [type number] Lists statistics and details of interface configuration.indb 360 6/1/16 12:02 PM .

145 defining.1w RSTP defined. 500-501 trunking.1x.1x. 146 switches as 802. 742 ABR (Area Border Router). 747 securing with IEEE 802. 190. verifying. 145 access-class command. verifying. 393 802.1D STP. 58.1Q. 145 EAP. 210-211 OSPFv2 multiarea configuration. 148-150 login authentication rules. 393 WANs. 209-210 OSPFv3 multiarea configuration. 625 access Internet. configuring. 628 3G wireless. 391 DSLs (digital subscriber lines).11 headers. 392-393 IPv6 restrictions. 147 TACACS+/RADIUS protocols. 486 6/1/16 12:04 PM . 145 username/password combinations. 745-746 private WANs. 149 9781587205798_BOOK.Index Symbols 2-way state (neighbor relationships).indb 852 enabling. 685 public cloud services Internet.1x authenticators. 389 cable Internet. 148 configuring for 802. 746-749 VPNs. 150 login process. 393 4G wireless. 145 aaS (as a Service). 20-21 headers. 145 authentication process. 62 802. 62 802. verifying. 149 username/passwords. 390-391 fiber. 58 port roles. 389 wireless WANs. 144-146 AAA servers. 60 port states. See ROAS 802. 149 AAA servers authentication configuration. 501 A aaa authentication login default command. 149 aaa new-model command. 625 interface OSPF areas. 186.

674-678 filtering ICMPv6 NDP messages. 471-472 numbered ACLs. 445. 452 permit. See ACLs Access Control Server (ACS). 668 ICMPv6 message filtering. 497 comparison of ACL types. 442-443 extended numbered ACLs configuration. 454-456 ACI (Application Centric Infrastructure). 683-684 IPv4 ACL. 666-667 limitations. 448 deny. 454 examples and logic explanations. 475-476 overview. 462 GRE tunnel issues. 670 standard. 156-157 access links MetroE. 365 MPLS. 147 access interfaces. 467 extended numbered ACL configuration commands. 671-674 testing. 448-449 tcp keyword. 563 9781587205798_BOOK. 777-778 classification. 669 extended. compared. 464 upd keyword. building. 467 keywords any. 24. 473-475 overview. and destination IP. 467-470 matching protocol. 679-683 filtering policies. 670 problems. 773-774 ACLs (access control lists). 677 tunneled traffic matching. 664-666 access-list commands. 448-449 log. 464 reverse engineering from ACL to address range. 668-669 implicit filtering ICMPv6 NDP messages.access control lists. 378 access-list command. compared. blocking. 678-679 access restrictions. 486 building ACLs with. 685 blocking. 476-477 IPv4. 464-467 overview. 496 SNMP security. 445.indb 853 implementation considerations. configuring. 463-464 matching TCP and UDP port numbers. 612 router originated packets. 472 editing. 463-466. 698 6/1/16 12:04 PM . 586 ACL Analysis tool. 685 prefix lengths. 683 capabilities. 670 management control. 669-670 logging. 666-667 IPv6. 440 QoS tools. 409-410 HSRP packets. 457. 440-441 matching packets. source IP. 670 location and direction. 441-442 named ACLs configuration. 113-114 access layer switches.

595 MAC. 445-446 matching subset of address. 448-452 list logic. 742 6/1/16 12:04 PM . 481-482 reversed source/destination IP address. 697 NMS polling. 696 notifications. 448 matching exact IP address. 481 inbound ACL filters routing protocol packets. verifying. 593 IPv4. 49 ADSL (asymmetric DSL). 480-481 ACL Analysis tool. 593 adjacent neighbors. 558 address blocks. 446-448 troubleshooting. 180. 595-597 connectivity. 479-480 common syntax mistakes. 502-503 agents (SNMP). 633 administrative distance. 448 alternate ports. 318 AF (Assured Forwarding). matching. 682 router configuration. 48 all IP addresses. 49 public cloud assignment services. 147 active HSRP routers. 186.indb 854 multicast. 242-243. 598-599 static route configuration. 91-92 Amazon Web Services (AWS). 600-603 9781587205798_BOOK. 454 command syntax. 452-453 wildcard masks. 445 configuration examples. 619 global unicast. 483-485 commands. 186-188 STA (spanning-tree algorithm).854 ACLs (access control lists) standard numbered ACLs access-list command. 599 unicast. 311-312 link-local. See prefixes addresses families. 593-595 link. 452-453 verification. 695 Get/Set messages. 477-479 ACL interactions with routergenerated packets. 477 ACL behavior in network. 646 IGP routing protocol algorithm. 391 advertising BGP routes. 406 unique local unicast. 303-304 eBPG enterprise public prefixes. 446-447 overview. 777-778 ACS (Access Control Server). 180 DUAL (Diffusing Update Algorithm). 696-697 algorithms Dijkstra SPF. 444-445 matching any/all addresses. 197 IPv6 assigning to hosts. 696 MIB. 443 reverse engineering from ACL to address range. 175 SPF (Shortest Path First). 307-308 subnets to ISPs. 454-456 troubleshooting. 177-178 administratively shutdown interfaces. 756-757 source/destination. 60-61.

777 controller.asymmetric DSL (ADSL) 855 American Registry for Internet Numbers (ARIN). 191 interarea routes. 174. 777-778 Path Trace app. 502-503 asymmetric DSL (ADSL). 190. 281 single-area. finding. 777 Application Centric Infrastructure (ACI). See ABR area design (OSPF). 174 BGP. 304 EIGRP. 174 AS (autonomous system). 190 benefits. 774 APIC EM (APIC Enterprise Module). 174 analyzers (network). 778 Path Trace ACL Analysis tool. 777 labs website. 765 ASNs (AS numbers). 188 SPF workload. 448 APIs (application programming interfaces). 770 APIC Enterprise Module (APIC-EM). 290-291 MPLS VPNs. 188. 248 for IPv6. 381 backbone routers. 391 6/1/16 12:04 PM . 381-382 network size. 777 Application Centric Infrastructure (ACI). 189-190 ABR. 768-769 APIC (Application Policy Infrastructure Controller). 765 architectures (SDN). 649 neighbors. 625 super. 777-778 Path Trace app. 498 application-specific integrated circuit (ASIC). 771-772 OpenFlow. 235. 394 any keyword. 304 as a Service (-aaS). 754 ASIC (application-specific integrated circuit). matching. 719 answering exam questions. 771 9781587205798_BOOK. 777 Path Trace ACL Analysis tool. 771 Area Border Router. 190 multiarea on ABR configuration. 190 intra-area routes. 190 three-area. 210-211 areas.indb 855 Open SDN Controller (OSC). 774-776 controller. 777 labs website. 189 ARIN (American Registry for Internet Numbers). 448 any/all IP addresses. 773-774 Application Policy Infrastructure Controller (APIC). 190 mismatches. 189 problems. reducing. 774 application signatures. 288 Assured Forwarding (AF). 190 internal routers. 742 ASAv (virtual ASA firewall). 776 Open SDN. 773-774 comparisons. 772 OpenDaylight (ODL). 774-776 ACL Analysis tool. 189-190 backbone areas. 790-792 anti-replay (Internet VPNs).

222. 216-217 least-bandwidth. 643 autonomous system (AS). 648 autosummarization. 491 MetroE. 147 TACACS+/RADIUS protocols. 359 defined. 304 auto-summary command. 381 backbone routers. 150 auth keyword (snmp-server group command). 356 SNMPv3. 237 managing.indb 856 B backbone areas (OSPF). 247 EIGRP for IPv4. 699. 216 higher. 393 PPP. 216-217 bandwidth command. 235. 342-343 PPP CHAP. 286 Internet VPNs. 185. 304 ASNs. 145 AAA servers configuration examples. 305-306 BGP (Border Gateway Protocol). 266-267 discontiguous classful networks. 174. 185. 152 types. 300. 247. 707-708 authentication ppp pap command. 148 EIGRP neighbors. 60. 267-268 AWS (Amazon Web Services). 259 interfaces defaults. 373-374 reference. 493 BDRs (backup DRs). tuning. 62-63 backup ports. 270 EIGRP. 650-651 metrics. 190 multiarea on ABR configuration. 145 auto-cost reference-bandwidth command. 643 batch traffic. 266 classful network boundaries. 211-212 Bellman-Ford protocols. See DV protocols best path selection (BGP). 267 defined. 303 AS. 217 OSPF costs based on. 707 authentication 802. 91-92 bandwidth EIGRP for IPv6 routes. 265 OSPFv3 interface. 270 EIGRP. 222.1x. 647 for IPv6. 742 9781587205798_BOOK. 625 super.856 attacks attacks DHCP-based. 211-212 backup port role (RSTP). 216. 174. 346 authenticators. 662 metrics. switches as. 265 routes. 150 login process. 148-150 login authentication rules. 237-239. 190 backup DRs (BDRs). 356 PPP PAP. 304 6/1/16 12:04 PM . 237.

156 CAC (Call Admission Control) tools. displaying. 305-306 configuring. 83 verifying. 49 root switch election. injecting. 83 global settings. 272 CCNA ICND2 200-105 Official Cert Guide Premium Edition eBook and Practice Test. 314 advertising subnets to ISPs. 342 6/1/16 12:04 PM . 304 ISP default routes. 531 challenge messages. 303 table entries. 792 CCNA ICND2 Config Labs website. 335 leased-line WANs. 766 CFN (Cisco Feature Navigator). 507 carrier Ethernet. 303 reachability. 50-52 verification. 311 BIDs (bridge IDs) STP. 808 binary wildcard masks. 313 prefixes. 92 Border Gateway Protocol. 796 CCNA Routing and Switching ICND2 Official Cert Guide website. 447 blocking state interfaces. See BGP BPDUs (bridge protocol data units). 790 CE (customer edge). 302 route advertising. 751 bridge IDs. 777 CCNA R&S practice exam. learning. 47-49 RSTP ports. 366 Catalyst switches RSTP modes.challenge messages 857 best path selection. 315-318 static discard routes. 45-47 burned-in MAC addresses. 82-83 9781587205798_BOOK. 505 CCENT/CCNA ICND1 100-105 Official Cert Guide. 88-89 CBWFQ (Class-Based Weighted Fair Queuing). See BIDs bridges. 77 system ID extensions. 391 cabling DTE cables. 751 private WAN connections. 749-752 email services traffic flow. 314 states.indb 857 branch offices public cloud example. 332-333 stacking cables. 319-320 update messages. 66 configuring. 750-751 Internet connections. See eBGP IGPs. See switches broadcast storms. 49 BPDU Guard. 49 C cable Internet. 73-74 binary-to-hexadecimal conversion. 303-304 routing table analysis reports website. 81 enabling/disabling. 377 centralized control planes. 303-310 bgp commands. 302 internal (iBGP). 88-90 Catalyst switches STP modes. 303 disabling. compared. 310 external. 318 classful network routes. 320-321 neighbors.

344-345 verifying. 106-108 Layer 3. 160 distribution/core switches high availability. 159-160 switch stacking. 496-497 NBAR. 496 routers. 267-268 routes. 749 nondisclosure agreement (NDA). 373.858 channel-group command (EtherChannels) channel-group command (EtherChannels). 35 virtual ASA firewall (ASAv). 756-757 cloud services catalogs. 177. 359 clocking. 505 Class of Service (CoS) fields (802. 772 Prime management products website. 497 matching. 349. 743-744 private. 177 clear ip ospf process command. 356 configuring. 159-161 CIR (committed information rate). 84. 757-758 Platform as a Service (PaaS). 739-741 6/1/16 12:04 PM . 95. 88-89 DevNet. 204. troubleshooting. 223 clear-text passwords. 788 Open SDN Controller (OSC). 495 ACLs. 541 channel service unit (CSU)/data service unit (DSU). 266 classic mode (EIGRP configuration). 88-90 Catalyst switches STP modes. 777 Feature Navigator (CFN). injecting. 747 DHCP services. 794-796 client VPNs. 732-733 Unified Communication Manager (CUCM). 159 benefits. 500-501 Class Selector (CS). 315-318 classful routing protocols. 498 router queuing.indb 858 Class-Based Weighted Fair Queuing (CBWFQ). 161 design. 740 Cloud Services Routers (CSRs). 754 9781587205798_BOOK. 147 Application Centric Infrastructure (ACI). 497 with marking. 396-397 clock rate commands. 757 Infrastructure as a Service (IaaS). 66 Catalyst switches RSTP modes. 695 server hardware. improving. 249 classification (QoS). 698 CLI skills. 773-774 BPDU Guard. 266-267 discontiguous. 332-334 CHAP (Challenge-Handshake Authentication Protocol) authentication. 497 classless routing protocols.1Q header). 531 Intercloud Fabric. 332 cloud computing address assignment services. 543 incorrect options. troubleshooting. 345-346 chassis aggregation. 503 classful networks autosummarization at boundaries. 509 Cisco Access Control Server (ACS). 742 NTP. 342.

commands 859 public. 643 9781587205798_BOOK. 237. 222 configure terminal. 457. 298 Hello/dead timer mismatches. 95. 149 aaa new-model. 662 EIGRP metrics. 96 6/1/16 12:04 PM . 84. troubleshooting. 750-751 intercloud exchanges. 486 any keyword. 748-749 Internet connections. 647 EIGRP for IPv6. 454-456 tcp keyword. 747 codecs. 445. 247. 464 upd keyword. 746-749 branch offices example. 486 access-list. 298 debug ip ospf hello. 467 log keyword. troubleshooting. 543 incorrect options. 267. troubleshooting. 747 accessing with private WANs. troubleshooting. 356. 445. 204. 222. 298 debug ip ospf adj. 741 accessing with Internet. 360 debug spanning-tree events. 467 extended numbered ACL configuration commands. 286. 149 access-class. 751 private WAN connections. 463-466. 454 deny keyword. 643 bgp. 448-449 examples and logic explanations. 754-756 email services traffic flow. 289 debug ip ospf events. 360 debug ppp negotiation. 349. 752-754 services. 106-108 Layer 3. 493 commands aaa authentication login default. 739 Software as a Service (SaaS). 289 debug ip ospf packet. 749-752 DNS services. 223 clock rate. 751 VNFs. 632 debug ppp authentication. 311 channel-group (EtherChannels). 745-746 accessing with private VPNs. 541 clear ip ospf process. 79. 298 debug ipv6 ospf adj. 743 Cloud Services Routers (CSRs). 452 permit keyword. 28 debug. 216. 648 bandwidth. 359 EIGRP. 359 command. 247 EIGRP for IPv4. 265 OSPFv3 interface. 346 auto-cost reference-bandwidth. 290 OSPF neighbors. 448 building ACLs with. 271 debug eigrp packets. 293 OSPF neighbors. 448-449 reverse engineering from ACL to address range. 286 debug eigrp fsm. 298 mismatched OSPF areas. 270 EIGRP.indb 859 auto-summary. 222. 464 authentication ppp pap. 270.

568. 615 interface. 543 interface range. 247. 297 ip route. 350. 600. 728 hostname. 648 ip helper-address. 297 ip mtu. 432 ip domain-lookup. 572 ip ospf.860 commands default-information originate. 417. 717 history enhanced interval. 543 interface dialer. 678 ipv6 access-list permit. 615 ipv6 access-list building. 359. 672 deny icmp any any. 265 extended IPv6 ACLs. 728 history buckets-kept 6. 615 ip access-group. 135 frequency. 196 MLPPP. 323 ip routing. 647 EIGRP for IPv6. 683 description. 270. 246. 247. 222 ip ospf cost. 477. 647 EIGRP for IPv6. 359 dialer pool. 270. 344. 598. 571 eigrp router-id. 543 ip sla. 321. 417. 637 ip name-server. 573-574 ip hold-time eigrp. 678-679 IPv6 ACLs. 196. 728 history lives-kept 1.indb 860 interface tunnel. 457. 432 interface loopback. 37. 345 icmp-echo. 525 encapsulation dot1q. 568. 222 interface multilink. 252 EIGRP. 214 delay. 473 ip address. 728 ip sla schedule. 728 history enhanced. 296. 543 encapsulation ppp. 297 ip ospf hello-interval. 662 EIGRP metrics. 467. 628 default-information originate always. 614 6/1/16 12:04 PM . 350 subinterfaces. 432 erase startup-config. 297. 450. 247. 223. 728 ip sla restart. 568. 525 ip address negotiated. 728 ifconfig. 572 ip hello-interval eigrp. 687 ipv6 access-list deny. 432 dns-server. 25. 584-585 IP addresses on loopback interfaces. 486 ip access-list. 418. 543 ip -6 neighbor show. 360 interface multilink1. 432 interface vlan. 222 ip ospf dead-interval. 728 history filter all. 237. 675 IPv6 ACLs. 662 encapsulation. 472. 270. 715 ipconfig. 400. 678 ipv6 address. 472-474 EIGRP. 350 interface port-channel. 600. 486 ip access-list extended. 27 9781587205798_BOOK.

673. 627. 715 no neighbor shutdown. injecting. 323 BGP table entries. 728 mtu. 248. 615 network BGP. 40. 270 6/1/16 12:04 PM . 294 ROAS subinterfaces. 251 OSPF interfaces as passive. 95 no spanning-tree portfast default. 643 ipv6 ospf cost. 647 9781587205798_BOOK. 648 EIGRP for IPv6 compatibility. 218 defined. 135 ndp -an. 246 EIGRP for IPv4. 476 no ip address. 647.commands 861 ipv6 dhcp relay destination. configuring. 314-320 EIGRP. 624. 647 EIGRP for IPv6. 543 routed ports. 268 no ip access-group. 354 OSPF processes. 222. 598 mac-address. 270 EIGRP support. 687 ipv6 unicast routing.indb 861 OSPF single-area configuration. 624. 650 Layer 1 leased-line WAN problems. 314 netsh interface ipv6 show neighbors. 196 OSPFv3. 539 Layer 3 switches. 662 EIGRP load balancing. 721. 314 no passive-interface. 263 OSPFv3. enabling. 643 ipv6 traffic-filter. 614 ipv6 unicast-routing. 651. 535 passive-interface. 270 no shutdown. 637 ipv6 ospf. 247. 205 defined. 527 no spanning-tree portfast bpduguard default. 614. 218 OSPFv2 multiarea configuration. 643 ipv6 router eigrp. 662 EIGRP for IPv6 routing. 40. 648. 198-200 OSPFv2 interface configuration. 359 EIGRP for IPv6. 539 no ip domain-lookup. 209 no auto-summary. 662 ipv6 hold-time eigrp. 223. 432 maximum-paths. 25. 662 ipv6 hello-interval eigrp. 662 ipv6 router ospf. 614. 322 neighbor shutdown. 614 ipv6 eigrp. 270 EIGRP. 572 no ip sla schedule 1. 222. 662 ipv6 mtu. 95 no switchport Layer 3 EtherChannels. 624 passive-interface default. 432 name. 297 EIGRP. 643 monitor session. 205. 615 neighbor. 270 EIGRP.

96. 346. 571-574. 487. 359 ppp authentication chap. 614 leased-line WANs. 352 OSPF interfaces. 222. 471-474. 614. 687 ping. 543. 647 router-id. 432 permit icmp any any routeradvertisement. 107. 643 RIDs. verifying. 472. 536 show interfaces description. 532 sdm prefer lanbase-routing. 352 show controllers serial. 569 EIGRP neighbor requirements. 41. 353 self-ping. 344 show interfaces status Layer 3 EtherChannels. troubleshooting. 687 show arp. 674 IPv6 connectivity. 457. 68 show access-list. testing. 615 IPv6 ACLs. 246. 432 ppp chap password. 360. 345 ppp chap hostname. 432 remark. 196. 417. 360 show etherchannel. 615 IPv6 host connectivity. 543 show IPv6 ACLs. 31-34. 359 pppoe-client dial-pool-number. 198 sdm prefer. 487 router bgp. 286 MLPPP. 539 routed ports. 473 show access-lists. 298. 275 STP status. 576 show interfaces dialer. 536 show interfaces switchport. 114-116. 311 router eigrp. 360 ppp multilink group 1. 602. 675 GRE tunnel ACLs. 350. testing. 350 ppp pap sent-username. 37. troubleshooting. 346 routed ports. 684 permit ipv6.862 commands permit. 640 PPP CHAP status. 624 OSPFv3. 433 show interfaces PPP status. 421. 684 permit icmp any any routersolicitation. 483. 349. 196 router ospf. 601 ppp authentication. 417. verifying. 543 show etherchannel 1 summary. 345 PPP PAP. 270. 450. 432 ppp multilink. 672 permit gre. 283 OSPF neighbors. 479. 483-485 ping6. 673 routing protocol-enabled interfaces. 432 pppoe enable.indb 862 router ospf 1. 360 ppp multilink group. 135 6/1/16 12:04 PM . 540 show interfaces. 289 OSPFv3 interface bandwidth. 572 show controllers. 298. 487 extended IPv6 ACLs. 222 9781587205798_BOOK. testing. 600 IPv6 routes. defining. 410 IPv6 ACLs. 86 show etherchannel summary.

211 Hello/dead timer mismatches. verifying. 211 neighbors. 450. 259. 297 EIGRP-enabled interfaces. 479. 405. 210 OSPF neighbors. 423 show interfaces vlan. 223. 271. 221 show ip ospf neighbor. 271. 313. 479 show ip interface brief. 262 successor routes. 271 metrics. 250. troubleshooting. identifying. 271. 293 OSPF areas for ABR interfaces. 352 show ip eigrp interfaces detail. 297 EIGRP enabled interfaces. 38. 433 show interfaces virtual-access. 323 show ip bgp summary. troubleshooting. 258 topology table. 474-476 show ip access-lists. 298 duplicate OSPF RIDs. 298 OSPF areas for ABR interfaces.commands 863 show interfaces trunk. 352 OSPF interfaces. 291 OSPF neighbors. 32-34. 206 show ip ospf interface brief. 275 OSPF neighbors. 223. 205. 298 DRs/BDRs details. 283 show ip interfaces. listing. displaying. verifying. 281 OSPFv2 interface configuration. troubleshooting. 288 OSPF processes shutdown. 223. 275 EIGRP neighbor requirements. 202 6/1/16 12:04 PM . 298 DRs/BDRs details. 450. 323 show ip eigrp interfaces. 289 OSPF status on interfaces. 360 GRE tunnels. 286 EIGRP neighbor status. 297 neighbor status. 201.indb 863 show ip ospf database. 433 show interfaces virtual-access configuration. 404 multilink interfaces. 250-251. 256 show ip eigrp topology all-links. 210 OSPF-enabled interfaces. 271 show ip eigrp neighbors. 260 show ip interface. 182. 457. troubleshooting. 289 9781587205798_BOOK. 253 IPv4 routing protocols. 286 show ip ospf. 295 show ip ospf neighbor interface brief. 286 multilink interfaces. 295 show ip protocols. displaying. 41. 289 OSPFv2 interface configuration. 223. 543 show ip access-list. 220 passive interface. 223 show ip ospf interface. 457. 253 neighbor verification checks. 285 show ip eigrp topology. 116-117 show interfaces tunnel. 179. 275 EIGRP neighbor requirements. 487 show ip bgp. displaying. displaying. 251-252. 223.

643 9781587205798_BOOK. 223. 425 EIGRP-learned routes. 729 show snmp host. 630 show ipv6 route. 662 show ipv6 eigrp interfaces detail. 614 IPv6 ACL ICMPv6 NDP message filtering. 271. 614. 703. 687 show ipv6 neighbors. 135. 75-77 6/1/16 12:04 PM . 729 show monitor session all. 353. 254 IPv4 routes added by OSPF. 663 show ipv6 routers. 638. 643 show ipv6 ospf database. 643 EIGRP for IPv6. 729 show snmp community. 643 show ipv6 ospf interface. 77. 360 show ppp multilink. 298. 83. 728 show snmp contact. 424. 178 dialer interface Layer 3 orientation. 681 IPv6 IPv4 replacement. 681 show mac address-table. 663 show ipv6 interface. 214 show ip sla enhanced-history distribution-statistics. 654 OSPFv3 interfaces. 81 show spanning-tree interface. 96 show spanning-tree bridge. 702. 643 EIGRP for IPv6. 643 show ipv6 ospf interface brief. 577-578 show ip route static. 729 show ip sla statistics. 728 show snmp group. 724. 577-580 administrative distance. 729 show ip sla summary. 663 show ipv6 eigrp topology. 635. 643 show ipv6 protocols. 81 show spanning-tree summary. 663 show ipv6 eigrp topology | section. 223. 96 show spanning-tree vlan 10. displaying. 630-631. 346-347. 297 show ip route ospf. 636.indb 864 show ipv6 ospf neighbor. 640. 663 IPv6 router connectivity. 114 show mac address-table dynamic. 729 show snmp location. 614. 709. 271. 614. 728 show snmp user. 96 show spanning-tree vlan. 96 show spanning-tree interface detail. 473-475 show snmp. 729 show monitor session. 708. 729 show ipv6 access-list. 717. 643 show ipv6 route | section. 543 show ip route eigrp. 603 show ipv6 ospf. 360 show pppoe session. 662 EIGRP for IPv6 interfaces. 724. 729 show ip sla history. 254. 201 routing tables. 640. displaying. 323. 82 show spanning-tree root. 219 show ip route. 729 show spanning-tree. 603 show ipv6 route eigrp. 654. 630. 687 show ipv6 eigrp interfaces. 433 show running-config. 662 show ipv6 eigrp neighbors. 449. 282-283 OSPFv2 interface configuration. 702. 663 show ipv6 route ospf. 614. 111 show monitor detail. 677. 723 show ppp all.864 commands OSPF configuration errors.

114 show vlan id. 26-29. 116 switchport mode dynamic desirable. 41. 294 ROAS subinterfaces. 55 spanning-tree portfast. 574 GRE tunnels. 727 snmp-server location. 27. 30. 30. 95 spanning-tree vlan. 141 shutdown. 141 show vlan brief. 141 show vtp status. 558 standby version. 527 shutdown vlan. 707 spanning-tree. 359 EIGRP for IPv6.indb 865 spanning-tree mode rapid-pvst. 406 IPv6 host connectivity. 37-38. 30. 28. 28-29. 74 spanning-tree vlan 10 port-priority 112. 727 snmp-server contact. 564 standby 1 preempt. 564 switchport Layer 3 switches. 95 spanning-tree bpduguard disable. 662 EIGRP for IPv6 routing. 88. 72. 139 switchport mode dynamic auto. 40 switchport mode access. 140 snmp-server. 554. 34. 81. 40. 72 spanning-tree mode pvst. 25. 313 show tcp summary. 72 9781587205798_BOOK. 727 snmp-server user. 95 spanning-tree bpduguard enable. 90 spanning-tree pathcost method long. 650 Layer 1 leased-line WAN problems. 727 snmp-server group. 354 OSPF processes. 116. 323 show vlan. 113. 139 switchport trunk allowed vlan. 83. 116. 565 show standby brief. 95 spanning-tree portfast bpduguard. 701. 95 spanning-tree mode. 559 standby version 1 | 2. 103 speed. 543 routed ports. 75. 41. 135 traceroute. 95 spanning-tree mode mst. 524 switchport nonegotiate. 77 show spanning-tree vlan 10 interface gigabitethernet0/2 state. 83. 527.commands 865 show spanning-tree vlan 10 bridge. 727 snmp-server enable traps. 114. 700 snmp-server community. 117 switchport trunk encapsulation. 565 show tcp brief. 40. 75. 710. 556. 92 show standby. 600 6/1/16 12:04 PM . 705 snmp-server host. 560. 114 show vlan status. 40. 95 spanning-tree portfast disable. 543 show vtp password. 41. 118 switchport voice vlan. 131. 135 switchport mode. 81. 41. 25. 135. 32 switchport mode trunk. testing. 95 spanning-tree portfast default. 555. 37-38. 134. 29. 135 show vlans. 40 switchport trunk native vlan. 576 standby. 40. 36-38. 134. 535 switchport access vlan.

406-407. 312-313 eBGP neighbors using link addresses. 698 confidentiality (Internet VPNs). 135 vtp password. 647 example. 270 EIGRP. 40. 475-476 standard numbered. 263.indb 866 configuring AAA servers. 29. 134. 247 verification. 246 ASNs. 247. 404 tunnel source. EIGRP configuration wildcard masks. 249 sample internetwork. 28 9781587205798_BOOK. 248 checklist. 651-652 route metrics. See verifying. 393 Config Checklist app. 448-452 BGP. 135 vlan 10. 137 vtp. 310 BPDU Guard. 145 ACLs (access control lists) extended numbered. 796 configure terminal command. 432 undebug all. 37. troubleshooting. 662 verification. 310 disabling eBGP neighbors. 651. 134. 611 IPv6 router connectivity. 615 tunnel destination. testing. 75 vlan. 148-150 AAA servers for 802.866 commands IPv6 network router problems. 140 vtp pruning. 140 vtp mode. 134. 698-699 Community-based SNMP Version 2 (SNMPv2c). 614 traceroute6. 320-321 table entries. 432 tunnel mode gre multipoint. 648-649 load balancing. 140 committed information rate (CIR). 699 community strings (SNMP). 615 tracert. 248-249 EIGRP for IPv6. 314-320 transporting messages with TCP. 647 commands. 248 classic versus named mode. 153-154 EIGRP. 134. 25. 311-312 ISP default routes. 509 communities (SNMP). 122 vlan 200.1x. injecting. 345. 432 tunnel mode gre ip. 652 6/1/16 12:04 PM . 135 vtp mode transparent. 134 vtp domain. 373. 359 variance. 81-83 DHCP snooping. 140 vtp version. learning. 602. 472 numbered. 310 update messages. 406-408. 647 EIGRP for IPv6. 314 eBGP neighbor verification. 29. 298 username. 140 vtp mode off. 246 classful network numbers. 40. 404. 650-651 timers. 467-470 named.

86-87 manual. 525 subinterfaces. 714-715 IGPs.indb 867 route selection metrics. 415-416 ISP router configuration example. 621 default routes. 627-628 load balancing. 554. 84 dynamic. 349-350 multiarea OSPFv2. 310 interfaces as passive. 702-704 6/1/16 12:04 PM . 197 matching with network command. 204-206 RIDs. 209 single-area configurations. 625 9781587205798_BOOK. 84-86 GRE tunnels. 524 native VLANs. 535-537 switching with SVIs. 337-340 HSRP. 418-419 verification. 537-539 switch routed ports. 699-701 Trap/Inform messages. 623-624 overlapping VLSM subnets. 599 ISL. 198 organization. 598 standard ACLs. creating. 701-702 verifying. 622 multiarea on ABR.configuring 867 EtherChannels. 344-345 PAP. 200-202 wildcard masks. 199 SNMPv2 Get/Set messages. 671-674 static routes. 526-527 single-area OSPFv2. 595-597 routing. 416-417 Layer 2. 721-724 MLPPP. 626 single-area. 525-526 subinterface numbers. 560-561 ICMP-Echo operations. 218-221 OSPFv3. 203-204 ROAS. 207-208 subnets. 210-212 OSPFv2 interfaces. 197-198 IPv4 addresses. 420-425 RIDs (OSPF). 528-529 verifying. 196-197 passive interfaces. 419 Layer 3 EtherChannels. 206 verifying. 417-418 summary. 198-200 multiarea configurations. 203-204 verifying. 343-344 CHAP. 584-585 PortFast. 598-599 extended ACLs. 402-404 HDLC. 524-525 troubleshooting. 346-347 PPPoE. 207-208 network command. 529-531 local SPAN. 206-210 network commands. 525 ISP routers. setting. 627 multiarea example. 81-83 PPP. 674-676 hosts. 205 IPv6 addressing on routers. 419 Layer 1.

766 networking devices. 512 TCP windowing. 135 9781587205798_BOOK. 36-38 full VLAN configuration example. 505 round robin scheduling. 504 prioritization. 771 Southbound Interfaces (SBIs). 751 Internet. 129 example. 747 contiguous networks. 707-708 groups. 78-79 PVST+. 55 verification commands. 137 default VTP settings. 710-711 requirements. 745-746 private WANs. 777 centralized control.indb 868 congestion avoidance. 129 storing configuration. 708-709 STP. 512-513 tools. 25-28 shorter VLAN configuration example. 766 APIC-EM. 74 port costs. 48. 72 options. 707-708 encryption. 239 DUAL process. 505-507 multiple queues. 73-74 topology changes. 763-764 control protocols (CP). 513-514 congestion management. 341 controllers. 105-106 6/1/16 12:04 PM . 28-29 trunking. 766 distributed. influencing. 746-749 VPNs. 766-767 Northbound Interfaces (NBIs). 267 control planes centralized. 711-712 users. 71 modes. 767-768 convergence EIGRP. 504 output queuing. 173 STP. 505 strategy. 507 connections (public cloud access) branch offices.868 configuring SNMPv3. 30-34 VTP common rejections. 241-242 routing protocols. 260-261 successors. 72-73 root election influence. 704 authentication. 705-707 notifications. 504 Low Latency Queuing (LLQ). 242-243 feasible successor routes. 707 verifying. 134-135 transparent mode. 75 VLANs (virtual LANs). 80-81 system ID extensions. 130 planning. 24-25 data and voice VLANs. 704 summary. 768-770 OpenDaylight SDN controller. troubleshooting. 74-75 per-VLAN port costs. 129 steps. 130-131 new VTP configuration settings.

charging for. 657-658 integrity. 735 workflow. 290 OSPF neighbors. 289 debug ip ospf events command. 503 CSRs (Cloud Services Routers). 131-133 DCE (data circuit-terminating equipment). 112-113 data terminal equipment (DTE). 636 MIB. troubleshooting. 179 area design. 695-697 OIDs. 762-763 STP impact on MAC tables. 697 variables. 373 bandwidth used. 201 exchanging between neighbors. 286 debug eigrp fsm command.indb 869 data plane EtherChannel impact on MAC tables. controlling. 735 physical networks. 374-375 data centers (virtual) networking. marking. 298 debug ip ospf adj command. 286.1Q header). 332 CS (Class Selector).debug ip ospf events command 869 converting binary to hexadecimal. 500-501 costs. 111-112 networking devices. 298 mismatched OSPF areas. 334 Dead Interval timer. 808 core switches. 334 9781587205798_BOOK. 492-493 EIGRP for IPv6 topology. 737-738 data circuit-terminating equipment (DCE). 184 dead timers. 293-294 debug command. 332-334 CUCM (Cisco Unified Communication Manager). monitoring. 334-335 databases LSDB. 503 CS DSCP values. 715-716 CP (control protocols). 179 OSPFv3. 180 contents. 736 vendors. 298 6/1/16 12:04 PM . displaying. 747 CSU/DSU (channel service unit/data service unit). 110 VLAN of incoming frames. 271 debug eigrp packets command. 159-160 CoS (Class of Service) fields (802. 697 variable numbering/names. 805-807 hexadecimal to binary. 377 D data application traffic. 190 best routes. 183-186 LSAs relationship. 808 decimal to binary. See metrics counters. 696 views. 393 usage (MetroE). finding. 35 customer edge (CE). 705 topology. 188 VLAN. 341 CPE (customer premises equipment). 373-374 overages.

networking. 372 MetroE physical. 189 OSPFv3 multiarea. 647 EIGRP for IPv6. See DPs designated routers. 675 IPv6 ACLs. 189 problems. 190. 400 deny command. 247. 491 delivery headers. matching. 190 intra-area routes. 79. 762 control. 719 devices. 377 MPLS VPNs Layer 3. 472-474. 370-371 E-Tree service. 190 three-area. 763-764 6/1/16 12:04 PM . 237. 365-366 MPLS Layer 3. centralizing. 160 Internet edge. troubleshooting. 214 default-information originate command. 289 debug ip ospf packet command. 281 single-area. 210-211 areas. 321 OSPF default routes. 448-449 dependencies (SPAN). 683 deny keyword. 214 OSPFv3. 190 internal routers. 406 destination IP. 360 debug ppp negotiation command. 265 managing. 650-651 metrics. 189 ABR. 188. 25 delay command. 371-372 E-Line service. 627-628 default VLANs. 766-767 control plane. 190 backbone routers. 223. 356. 261 debug ppp authentication command. 298 Hello/dead timer mismatches. 381-382 network size. 190 benefits. 360 debug spanning-tree events command. 672 deny icmp any any command. See DRs destination addresses. 722 9781587205798_BOOK.indb 870 description command. 96 decimal-to-binary conversion. 189-190 backbone areas. 306 MetroE Layer 3. 622 designated ports. 628 default routes. 188 SPF workload. 446-447 default-information originate always command. 442. 191 interarea routes. 805-807 decimal wildcard masks. 293 OSPF neighbors. 237. 662 EIGRP metrics. 270 EIGRP. 632 debug messages. 298 debug ipv6 ospf adj command. 487 extended IPv6 ACLs. 190 MPLS VPNs. 463-464 destination ports (SPAN). 370 E-LAN service.870 debug ip ospf hello command debug ip ospf hello command. 379-382 OSPF area. reducing. 265 delays EIGRP IPv6 routes. 359 design improving with chassis aggregation.

425 PPPoE configuration. configuring. 152 DHCP Binding Table. 777 DHCP (Dynamic Host Control Protocol) Binding Table. 390-391 9781587205798_BOOK. 762-763 management plane. chassis aggregation 871 data plane. 153 DHCP-based attacks. 159-160 6/1/16 12:04 PM . 255-257 LSDB contents. 267 discovery (EIGRP neighbors). 334 Digital Signal level 1 (DS1). 765-766 DevNet. 153 trusted/untrusted ports. See DSCP Diffusing Update Algorithm (DUAL). 139 discard routes. 266-268 discontiguous networks.indb 871 Dijkstra SPF algorithm. 180 direction (ACLs). 275 IPv4 routing table. 83 TCP connections. 764 switch internal processing. 573 public cloud services. 417. 646 Digital Signal level 0 (DS0). 319 discarding state interfaces. 153 features. 83 ports. 116 EIGRP for IPv6 routing. 61 discontiguous classful networks.distribution switches. 650 PortFast. See DV protocols distributed control planes. 440-441 disabling BGP neighbors. 313 distance vector protocols. 421-422 dialer pool command. 211 EIGRP enabled interfaces. 234 displaying BPDU Guard global settings. 596 dialer interfaces Layer 3 orientation. 151-154 stateful. 151 ports as trusted. 253 topology table. 416-417 verifying. 608-609 troubleshooting. 757 snooping configuration settings. 334 digital subscriber lines (DSLs). 152 DHCPv6. 60 VLANs. 47-49 RSTP. 201 OSPF-enabled interfaces. 314 BPDU Guard. 253-254 neighbor status. 242-243. 83 DTP. 153 DHCP Relay. 766 distribution switches. 275 passive interfaces. 334 Digital Signal level 3 (DS3). chassis aggregation. 154 rules summary. 114-115 VLAN trunking. 206 PortFast global settings. 432 Differentiated Services Code Point. 573-574 DHCP-based attacks. 153 rate limiting. 83 DRs/BDRs details.

334-335 DTP (Dynamic Trunking Protocol). 390 DTE (data terminal equipment). 412-413 DNS (Domain Name System) IPv6 network troubleshooting. 49. 146 EAPoL (EAP over LAN). 754-756 troubleshooting. 105 DR (designated router). 411 multipoint GRE tunnels. 306 enterprise public prefixes. 104-105 problems. 185-186 DROthers routers. 619 OSPFv3 address families. 501 marking values AF. 229-230 dynamic EtherChannels configuration. 304 Internet edge. 232-233 route poisoning. 503 EF. 502 DSL (digital subscriber line). 228 distance/vector information learned. 211-212 Ethernet links. 306 dual stack OSPFv2/OSPFv3. learning. 116 E E1. 228 EIGRP as. 231-232 split horizon. 620 strategies. 571-572 dns-server command. 571 down status (interfaces). 230-231 update messages. 306 design. 54. 146 earplugs (exam). 116 9781587205798_BOOK. See DHCP Dynamic Multipoint VPN. 334 E3. 334 DS1 (Digital Signal level 1). 334 EAP (Extensible Authentication Protocol). See DMVPN Dynamic Trunking Protocol (DTP). 86-87 Dynamic Host Control Protocol. 185 discovering. 598 DV (distance vector) protocols. 390-391 DSLAMs (DSL access multiplexers). 502-503 CS. advertising. LAN segments. 186 DS0 (Digital Signal level 0). 411 NHRP (Next Hop Resolution Protocol).indb 872 DUAL (Diffusing Update Algorithm). 334 DSCP (Differentiated Services Code Point). 309 6/1/16 12:04 PM . 354 DP (designated port). troubleshooting. 334 DS3 (Digital Signal level 3). 175. 242-243. 786 eBGP (External BGP). 185 backup (BDRs). 607-608 public cloud services. 60 choosing. 497 fields (QoS marking). 307-308 ISP default routes. 646 dual Internet edge design.872 DMVPN (Dynamic Multipoint VPN) DMVPN (Dynamic Multipoint VPN).

234-235 discovery. 234 requirements. 302 interfaces configuration problems. 265 EIGRP topology database. 253 topology information. 285-286 OSPF. 262 example. 260-261 identifying. 235-236 troubleshooting example. compared.indb 873 873 EIGRP for IPv6. 286 autosummarization. 262 delay settings. 173. 252 RIP metrics. 248-249 convergence. 240-241 RD (reported distance). 246 classful network numbers. 286 metrics. 176 6/1/16 12:04 PM . 502 EF RFC (RFC 3246). configuring. 246 ASNs. compared. 314 using link addresses. 286-288 verifying. 237-238 FD (feasible distance). 275 OSPF interfaces. 260-261 successors. 240-241 route load balancing. 241-242 disadvantages. 224 query/reply messages. 653 feasible successor routes convergence. 247 wildcard masks. 63 EF (Expedited Forwarding). 249 sample internetwork. 382 neighbors. 275-281 K-values. 233. configuring. 248 classic versus named mode. 227 configuration. compared. exchanging. 236 bandwidth. 238-239 MPLS VPN challenges. 284-286 status. 502 EGP (exterior gateway protocol). 266 classful network boundaries. 501 EF DSCP value marking. 311 verifying. 264 serial link bandwidth. 278-281 identifying. compared. 302 EIGRP (Enhanced Interior Gateway Routing Protocol). 266-267 discontiguous classful networks. 235. 267-268 benefits. 242 RIDs. 744 edge ports. 236-237 components. 312 disabling.EIGRP for IPv4 neighbors configuring. 175 EIGRP for IPv4 as advanced DV protocol. 248 checklist. 312-313 Eclipse IDE. 281 troubleshooting. 242-243 feasible successor routes. 239 DUAL process. 258-260 goals. 644-646. 232-233 authentication. 265 calculation. 227 9781587205798_BOOK.

699. 647 example. 359. 250-252 IPv4 routing table. 657-658 eigrp router-id command. 115 Encapsulated RSPAN (ERSPAN). 83 PPPoE. 659-660 topology data. 234 load balancing. 525 encapsulation dot1q command. 252. 653 FS. 198 PortFast. See also EIGRP for IPv4. 644-646. 717 Enhanced Interior Gateway Routing Protocol (EIGRP). displaying. 255-257 variance. 367-371 email. 417. 773 enhanced history. 662 E-LAN (Ethernet LAN) service. 417 VLANs.874 EIGRP for IPv4 RIPv2/OSPFv2. 350. 149 BPDU Guard. identifying. 395 SNMPv3. 263-264 successor routes. 432 encryption IPsec. 249 EIGRP enabled interfaces. 647. 494 end-user traffic. 651-652 route metrics. 656-657 routes ASNs. 654-655 neighbors. 246. 368-372 E-Line (Ethernet Line) service. 721 encapsulation command. 650 FS. 707-708 tunnel VPNs. 395-396 keys. compared. finding.indb 874 troubleshooting. 543 encapsulation ppp command. 652 DUAL. 647 commands. 263-264 verification. 257-258 topology database metrics. 598 OSPF configuration mode. 233 routes choosing. 262 exchange. Second Edition (Cisco Press). 253 EIGRP for IPv6 configuration. 660 verifying. 648-649 load balancing. 650-651 timers. displaying. 253-254 neighbor status. 259 variance. compared. 234 table. 713 endpoints. 646 interfaces. 646 EIGRP for IPv4. 395 End-to-End QoS Network Design. displaying. 750-751 enabling AAA servers. 344. 649 enabling/disabling. 175. 246 EIGRP for IPv6 routing. measuring. 646 9781587205798_BOOK. EIGRP for IPv6 6/1/16 12:04 PM . 83 EIGRP. 263-264 tuning with bandwidth changes. 650 IPv6 routing. 646 successors.

539-540 MAC tables impact. 18 IP telephony. 784-785 6/1/16 12:04 PM .11 headers. 790-791 CCNA R&S. 790 checklist. 106 configuration checks before adding interfaces. 465 erase startup-config command. 721 EtherChannels. 20 overview. 597-599 EVC (Ethernet Virtual Connection). 21-24 tagging. 792-793 practice exams answering questions. 111-112 troubleshooting. finding. 16-18 routing between. 84-86 Layer 3 configuring. 494 enterprises. 787 knowledge gaps. 366 links. 786 tutorial. 445-446 exam CLI skills. 372 ETSI (European Telco standards body). 64-65 configuring. 785 time-check method. 797-798 time budget versus number of questions. 25 IDs. 747 Ethernet LANs service. 794-796 earplugs. 29-34 Ethernet Line (E-Line) service. 500-501 802. 366 IEEE standards. 796-797 study tasks. 106-108 Ethernet 802. 24-29 default VLANs. 135 ERSPAN (Encapsulated RSPAN). 365 carrier.1Q headers. 798 studying after failing to pass.indb 875 875 native VLANs. 784 ready to pass assessment. 367 exact IP address matching. 86-87 manual. 108-109 incorrect options. 575-576 VLANs (virtual LANs) configuration. 790 ICND2. 367-371 E-Tree (Ethernet Tree) service. 790 other. 788 question types. 34-39 9781587205798_BOOK.exam Enterprise QoS Solution Reference Network Design Guide. 18-21. 501 access links. 185-186 WANs. 786-787 preparing for failure. 368-372 troubleshooting. 369. 541 verifying. 789-790 pre-exam suggestions. 754 EUI-64 rules. classification matching. predicting. 792 taking. 18-20 trunking. 496-497 eq 21 parameters. 786 exam-day suggestions. 537-539 troubleshooting. 797 scores. 84 dynamic.

557 with preemption. 554 failover. 553 no preemption. source IP. 258-260 FHRP (First Hop Redundancy Protocol). 241-242 convergence. 501 extended IPv6 ACLs configuring. 49 failing the exam. 555 load balancing. 558 troubleshooting. 260 feasible successor (FS). 604 finding EIGRP enabled interfaces. choosing. 180 wildcard masks. 393 FIFO (first-in. 302 external BGP. 464-467 Extensible Authentication Protocol (EAP). 290-291 routers best routes. 448 firewalls. 674-676 examples. 550 9781587205798_BOOK. 549 options. 260-261 identifying. 551 active/passive model. 293 OSPF area mismatches. 463-464 matching TCP and UDP port numbers. 799 failed interfaces. 551 active/standby routers. 462 configuration. 550-551 fiber Internet. 146 exterior gateway protocol (EGP). See eBGP F Facebook (Wendell Odom). 467-470 matching protocol. 754 First Hop Redundancy Protocol. 240-241. 250-252 feasible successor routes. 336 FD (feasible distance). 555-556 versions. 356 FCS (Frame Check Sequence). 356 HSRP. 257-258 mismatched Hello/dead timers. 355 PAP authentication. 676-678 extended numbered IPv4 ACLs. 557 configuring. 552 keepalive. 668-669. 173.876 Expedited Forwarding (EF) Expedited Forwarding (EF). 544 features. 552 group numbers. 504 filtering ICMPv6 messages. 559-560 need for. 788. 256 feasibility conditions. 560-563 verifying. 555 active/standby rules. 242. and destination IP. 668 issues. 797-798 failures CHAP authentication. See FHRP 6/1/16 12:04 PM .indb 876 HSRP. 679-683 IPv6 ACL policies. 646 feasible successor routes. 258-260 successor routes. first-out).

406 tunnel destination. 404 functionality. 229. displaying. 334 Frame Check Sequence (FCS). 235 full VLAN configuration example. 112-113 looping. See routing interface state. 179 flow networking. 398 GRE numbers (HSRP) first-in. 628 full updates. 158 flooding. 593 Google App Engine PaaS. 158 FlexStack-Plus. 750-751 Forward delay timer (STP). 334 Fractional T3. first-out (FIFO). 186. 699 SNMPv2 support. 411 point-to-point. 646 full drops. 25-28 fully adjacent neighbors. 399 routes. preventing. 555 6/1/16 12:04 PM . 398 “Get IEEE 802” program. 504 FlexStack. 399 configuring. 407 Layer 3 issues. 402-404 details. 411 multipoint with DMVPN. 777-778 forwarding plane. 404-406 group numbers (HSRP). 406 large scale environments.indb 877 877 G generic routing encapsulation (GRE). 405 troubleshooting. 47-49 paths. 368 full neighbor state. 336 Frame Relay. 493 public cloud traffic. 696 RO/RW communities. 398 unsecured networks. 699-701 GLBP (Gateway Load Balancing Protocol). 728 FS (feasible successor). 406 ACLs. 398 between routers. 336 incoming. 495 HDLC. 408 tunnel interfaces. 409 source/destination addresses. 56 forwarding data. 633 9781587205798_BOOK. 409-410 interface state. 400-401 verifying. 514 full mesh topology (MetroE). 59 Get messages agent information. 113 frequency command. testing. 744 GRE (generic routing encapsulation). See data plane Fractional T1. 341 switching. 47 PPP. 544 global unicast addresses. 45-47 defined. 362 frames broadcast storms. 186. 44 multiple frame transmissions.

600-601 issues. 233 Hello messages (OSPF). 571-572 ensuring IPv4 settings match. 552 group numbers. 551 active/passive model. 400 IP. 398 headers 802. 597 routes. 728 history lives-kept 1 command. 717 OSPF. 336-340.1Q.878 groups groups endpoint. 728 history filter all command. 705-707 MIB views. 717 9781587205798_BOOK. 557 configuring. 554 failover. 705 write views. 49 Hello Interval. 357 server virtualization. 56 hexadecimal-to-binary conversion. 501 delivery. 716 history IP SLA data. 608-610 name resolution problems. 345 hosts IPv6. 501 Hello BPDU. verifying. 728 Hold Interval. 233 hostname command. 551 active/standby routers. 332 historical success/failure counters (IP SLAs). 607-608 pings fail from default router. 619 SNMP. 595 connectivity. 544. 181-182 Hello timer dead timer mismatches. troubleshooting. 695 history buckets-kept 6 command. 500-501 802. 184. 293-294 STP. 596 stateless address autoconfiguration (SLAAC). 705 security levels. 569-571 HSRP (Hot Standby Router Protocol).indb 878 history enhanced interval command. 499-501 MPLS Label. 555 active/standby rules. 568-569 mismatched masks. 706 H HDLC (High-level Data Link Control). 808 high availability. 555 6/1/16 12:04 PM . 605-606 stateful DHCPv6. 336-340. 728 history enhanced command. 606-607 pings only working in some cases. 604 missing settings. 331. 572 DNS problems. choosing. 773 SNMPv3. 159-160 High-level Data Link Control (HDLC). 331.11. 398 High-speed WICs (HWICs). 734 troubleshooting IPv4 settings default router IP address setting.

303 HWICs (High-speed WICs). 303 IGRP (Interior Gateway Routing Protocol). 562 verifying. 332 hypervisors. 366 “Get IEEE 802” program. 559 hub and spoke topology (MetroE). 177 configuring. 175 implicit filtering. assigning. 369 Huston. 59 ifconfig command. See practice exams IEEE (Institute of Electrical and Electronics Engineers) 802. 553 no preemption. matching. 563 configuration. compared. 675 9781587205798_BOOK.1D standard. 112-113 inferior Hello.1x access. 58 802. 563 misconfiguration symptoms. 674 messages. 315-318 static discard routes. 302 metrics. 174 ASNs. filtering. 728 ICMP-Echo operations. 557 with preemption. 304 icmp-echo command. 55 Ethernet standards. securing. 145 LAN access. 314 advertising subnets to ISPs. 175 subnets. 734 I IaaS (Infrastructure as a Service). 561 routers configuring different VIPs.injecting BGP table entries 879 load balancing. securing. 742 IANA (Internet Assigned Numbers Authority).1w amendment. 481 ICMPv6 Echo Request messages. 558 troubleshooting. 668-684 packets. 58 802. 568. 226 BGPs. 173. 682 website. 600. 310 goals. 231 Inform messages. 615 IGP (interior gateway protocol). 696-697 SNMPv2. 319-320 6/1/16 12:04 PM . 174 ICMPv6 parameters. 555-556 versions. 713 icmp keyword. 144-145 authenticators. 302 classless/classful. 560 ACL blocks HSRP packets. 683-684 incoming frames. 58 802. 701-702 SNMPv3. 175-176 routing protocol algorithm. 145-146 default port costs. 560-561 group number mismatches. 318 classful network routes. 742 injecting BGP table entries. Geoff website. 710-711 Infrastructure as a Service (IaaS).indb 879 ICND2 practice exam. 669 IPv6 multicast address space registry website. 563 version mismatches. 174 iBGP (Internal BGP). 714-715 ICMP Echo probe. 50 infinity.1D Spanning-Tree states. 559-560 HSRPv2 (HSRP version 2).

543 interface range command. 25. 216-217 EIGRP interfaces. 113-114 administratively shutdown. 190. 175 interactive data application traffic.indb 880 down status. setting. 654-655 EtherChannels. 250-252. 349 Northbound (NBIs). 360 interface multilink 1 command. 354 EIGRP configuration problems. 281 identifying. 281 troubleshooting. 416-417. 492 interactive voice traffic. 47 delays. 204-206 OSFPv3. 278-281 enabled. 203 multilink. 638-640 passive EIGRP. 47 LAN speeds. 259 higher reference. tuning. 219-221 OSPFv3. 626 troubleshooting. 630 influence route selections. compared. compared. 640 intercloud exchanges. adding. 37. 265 dialer Layer 3 orientation. 58 listening state. 631-632 verifying. 196. 265 EIGRP routes.880 instantiating VMs instantiating VMs. 400. verifying. 218 verifying. 210-211 access. 494 interarea routes. 275 passive. 275-281 EIGRP for IPv6. 490 learning state. 74 6/1/16 12:04 PM . 281-283 OSPFv2 configuration. 543 interface dialer command. 222 interface multilink command. 630-631. 543 interfaces ABR OSPF areas. 432 interface loopback command. 425 PPPoE. 624 per-VLAN STP costs. 216 EIGRP metric calculations. 748-749 Intercloud Fabric. 742 Institute of Electrical and Electronics Engineers. 27 interface tunnel command. 275 OSPF interfaces. 768-769 bandwidth defaults. setting. 218 example. 196 troubleshooting. 216-217 blocking state. 350 interface port-channel command. 212. 217 OSPF costs based on. 108-109 failed. 49 forwarding state. 421-422 9781587205798_BOOK. 216 costs. 432 interface vlan command. 768-770 OSPF bandwidth. finding. 58 loopback. 251 OSPF. 749 interface command. See IEEE Integrated Intermediate System to Intermediate System (IS-IS). 49 application programming (APIs).

394 clients. 389 benefits. 398 state. 274 Southbound (SBIs). 477. 423 VLAN. 233 internal BGP (iBGP). 190. 584-585 IP addresses on loopback interfaces. 623-624 Internet access. 190 ip -6 neighbor show command. 391 DSLs (digital subscriber lines). 198 6/1/16 12:04 PM . 48-49 status codes. verifying.indb 881 edge. 392-393 9781587205798_BOOK. 432 ip_address parameter (network command). 389 wireless WANs. 57-58 forwarding or blocking criteria. 407 virtual-access. 20-21. 467. learning. 486 ip access-list command. 535-537 routing protocol-enabled. 396-397 security. 306 enterprise public prefixes. 450. See ACLs ip address command. See SVIs tunnel ACLs. 400 destinations. 745-746 computing branch office connections. 389 cable Internet. 767-768 states changing with STP. 393 WANs. 765-766 internal routers. 486 ip access-list extended command. 393 Internet Assigned Numbers Authority. See ISPs Inter-Switch Link (ISL). eBGP and. 525 intra-area routes. 350 subinterfaces. 568. See IANA Internet service providers. 409-410 creating. 751 VPNs. 390-391 fiber. 409 replacing serial links. See IGP Interior Gateway Routing Protocol (IGRP). 472. 524-527 switched virtual. 196 MLPPP. 525 ip address negotiated command. 395-396 as WAN service. 389 wireless. See SVIs WANs. 306 design. 304 internal processing (switches). 393 site-to-site. 307-308 ISP default routes. 353 subinterfaces. 408 Layer 3 issues. 457. 615 ip access-group command. 490 working.ip_address parameter (network command) 881 routed. 49 interior gateway protocol. 309 public cloud accessing. advertising. 175 interior IP routing protocols. 418. 473 IP ACLs (access control lists).

717 UDP Jitter probes. 253 Layer 3 EtherChannels configuring. 263-264 verifying. 637 ip name-server command. 715-716 history data. finding. 756-757 DHCP services. 395-396 IPv4 routing ACLs. 36-38 summary. 248-249 load balancing. 648 ip helper-address command. 501-503 IPsec. 572 IP headers. 808 decimal-to-binary. 713 sources. 297. 197. 666-667 addresses. 38-39 ipconfig command. 531 6/1/16 12:04 PM . 713 responders. 296. 247. 34 data and voice VLAN concepts. 728 ip sla restart command. 532-534 verifying. 717 ICMP-Echo. 253-254 neighbor status. 222 ip ospf dead-interval command. 573-574 ip hold-time eigrp command. 529-531 troubleshooting. 713 ip sla schedule command. 713-715 operations. 600. displaying. 715 IP telephony (VLANs). 222 ip ospf cost command. 539-540 Layer 3 switch routed ports. 323 ip routing command. 713 9781587205798_BOOK. 297 IP IGP metrics. 499-501 ip hello-interval eigrp command. 568. 712 historical success/failure counters.882 IP addressing IP addressing conversions binary-to-hexadecimal. 757 ip domain-lookup command. 270. 270. 250-252 IPv4 routing table. 572 ip ospf command. 534-537 Layer 3 switching with SVIs configuring. 537-539 troubleshooting. 543 ip sla command. 808 public clouds address assignment services. 175-176 ip mtu command. 297 ip route command. 716 history data. 805-807 hexadecimal-to-binary. 541 verifying. 249 EIGRP enabled interfaces. 247.indb 882 troubleshooting with counters. 615 IPP (IP Precedence) fields (QoS marking). 253-254 EIGRP verification. 297 ip ospf hello-interval command. displaying. 34-36 data and voice VLAN configuration and verification. troubleshooting with. 619 EIGRP configuration. 728 IP SLAs (IP Service Level Agreements).

670 standard. 647. 575-576 mismatched IPv4 settings. 678-679 IPv6 ACLs. 573-574 DNS problems. 448 exact IP address. verifying. 662 ipv6 router ospf command. 670 addressing on routers configuration. 669 extended. 683 capabilities. 624. 674-678 filtering ICMPv6 NDP messages. 678-679 access restrictions. 677 tunneled traffic matching. 581-585 IP forwarding issues. 600-601 hosts. 586 router WAN interface status. 678 ipv6 access-list permit command. 624. 572 DHCP issues. 685 blocking. 614. 670 management control. 273-274 subnet masks mismatched masks. 445-446 subset of address. 598-599 connectivity. 614 ipv6 eigrp command. 201 QoS marking. 643 ipv6 ospf cost command.IPv6 routing matching addresses any/all addresses. 499 routing protocols displaying. 614. 614 ipv6 dhcp relay destination command. 670 problems. 679-683 filtering policies. 687 ipv6 access-list deny command. 569-571 packet filtering with access lists. 446-447 OSPF added. 643 IPv6 routing access restrictions with IPv6 ACLs. building. 637 ipv6 ospf command. 662 ipv6 hello-interval eigrp command. 662 ipv6 mtu command.indb 883 883 ipv6 hold-time eigrp command. 685 prefix lengths. 671-674 testing. configuring. 572 default router IP address setting. 568-569 mismatched masks. 683-684 IPv4 ACL. 685 ACLs. 585 ipv6 access-list commands building. 664-666 access-list commands. 202 troubleshooting. 571-572 incorrect addressing plans. 581 troubleshooting. 601-603 6/1/16 12:04 PM . 648. 569-571 VLSM (variable length subnet masking). 577-580 LAN issues. 662 9781587205798_BOOK. 598. 612 router originated packets. 643 ipv6 router eigrp command. 668 ICMPv6 message filtering. 668-669 implicit filtering ICMPv6 NDP messages. 678 ipv6 address command. 600-601 routers. compared. 669-670 logging. 666-667 limitations.

636-638 IPv6 routes. 607-608 router issues. 650-651 OSPFv3 metrics. troubleshooting. 646 timers. 657-658 global unicast addresses. 628-629 passive interfaces. enabling. 500 routers. 604 host pings fail from default router. 627-628 interface cost metrics. 604 host issues. 595 stateful DHCPv6. 651-652 neighbors. 605-606 missing IPv6 settings in host. 644-646. 595 multicast addresses. 631-632 troubleshooting neighbors. 604 routing.indb 884 OSPFv2. 619 QoS marking. 624 RIDs. 630-631 verifying neighbors. 632-633 protocols. compared. 638-640 interfaces. 646 EIGRP for IPv4. 646 interfaces. 632 9781587205798_BOOK. 612 filtering issues. 621-622 default routes. 654-655 load balancing. compared. 593 static route configuration. 638-640 troubleshooting. 625 neighbors. 630 IPv6 MTU mismatches. 647-649 DUAL. 604 ACLs. 659-660 successors. 636 LSDBs. 627 LSAs. 593-595 6/1/16 12:04 PM . 624 route selection metrics. 593 unique local unicast addresses. 599 subnetting. 640-641 subnetting. 611-612 unicast addresses. 623-624 troubleshooting interfaces. 640-641 load balancing. 596 stateless address autoconfiguration (SLAAC). 650-651.884 IPv6 routing EIGRP ASNs. 626 single-area configuration. 619-620 OSPFv3 configuration. 598 routes EIGRP for IPv6 metrics. 653 FS. 656-657 routes. 636 multiarea on ABR configuration. 626. 652 topology data. 608-610 name resolution problems. 682 OSPF. 606-607 host pings only working in some cases. 633-635 verifying interfaces. 593-594 troubleshooting. 621. 597 link-local addresses. 649 configuration. 593 host configuration.

687 ipv6 unicast routing command. 86 LANs. 335-336 PPPoE configuration. 670 permit. 42 security IEEE 802. 309 router configuration example. 442. 575-576 VLAN support. 334 physical components. 464 knowledge gaps. 144-146 STP security exposures. 427-428 Layer 2 leased-line WANs. video display. 417 troubleshooting. 614 IS-IS (Integrated Intermediate System to Intermediate System). video display. learning. 792-793 K-values (EIGRP). 523 defined. 54. 354-356 leased-lines with HDLC. 795-796 LACP (Link Aggregation Control Protocol). 491 K keepalive failures. 416-417 switches. 464 udp.1x. 349 PPPoE configuration. 20-21. 320-321 dial connections with PPP. 744 jitter. 414 Internet edge. 598. 733 9781587205798_BOOK. 333-334 troubleshooting. or mouse).Layer 2 ipv6 traffic-filter command. 481 log. 428-429 6/1/16 12:04 PM . finding. 332-333 speeds. 389 default routes. 448-449 tcp. See also commands any. 395 keywords. 733 keys (encryption). 354 leased-line WANs with HDLC. 336 MLPPP. 419 subnets. 104-105 interfaces.indb 885 885 L labs. completing. 65-66 troubleshooting. 16 DPs. 490 redundancy problems caused without STP. 286 KVM (keyboard. 525 ISPs (Internet service providers). 21 troubleshooting. managing. or mouse (KVM). 175 ISL (Inter-Switch Link). 448-449 icmp. 122 Layer 1 leased-line WANs CSU/DSUs. 442. 45-46 STP. 673. 318 J Jenkins continuous integration and automation tool. learning. 355 keyboard. adding. 448 deny. advertising. 452.

63 serial bandwidth. 378 addresses. 348-349 MPLS. 341 multilink. 175. 370-371 E-Tree service. See MLPPP PPP functions. 725 Link Aggregation Control Protocol (LACP). 238-239 replacing with IP tunnels. 341-342 learning state (interfaces). 335-336 CSU/DSU. See LSDB link-state protocols. 382 OSPF area design. 237 limiting SPAN sources. 23-24 LCP (Link Control Protocol). 505-507 6/1/16 12:04 PM . 183 links access MetroE. 529-534 VLAN (virtual LAN) routing. 336 physical components. 330-331 building. 354 Layer 2 problems. 381-382 PPPoE configuration. 185-186 RSTP types. 595 link-state advertisements. 357-358 mismatched subnets. See also OSPF Link-State Update (LSU) packets. 353-354 Layer 1 problems. 379-380 EIGRP challenges. 341 framing. 537-541 routed ports. 333-334 troubleshooting. 377 MPLS VPNs. 534-537 with SVIs.886 Layer 3 Layer 3 GRE tunnel issues. 311-312 Ethernet. 344-346 configuring PPP PAP.indb 886 configuring PPP CHAP. 357-358 MetroE design. 86 Link Control Protocol (LCP). 429 switches. 370 E-LAN service. 417-418 status. 358 least-bandwidth. 342-343 configuring PPP. 365 MPLS. 58 leased-line WANs. 341-342 link-local addresses. 21 EtherChannels. troubleshooting. 343-344 9781587205798_BOOK. See LSAs link-state database. 425 troubleshooting. 398 list logic (IP ACLs). 354-356 Layer 3 problems. 340 speeds. 346-347 control protocols. 371-372 E-Line service. 398 routing IP packets over. 334 with HDLC. 336 configuring HDLC. 444-445 listening state (interfaces). 372 MLPPP. verifying. 332-333 with PPP authentication. 409 leased-line WANs. 58 LLQ (Low Latency Queuing). 337-340 de-encapsulating/ re-encapsulating IP packets. 336 framing.

179 OSPFv3. 183 LTE (Long-Term Evolution). 217 OSPFv3. 179 OSPFv3. 636 router. 185-186 maintenance. 111 tables EtherChannel impact. displaying. 179 LSDB relationship. 670 logical switches. 111 learning. 84-86 marking. 203 looping frames. 110 maintenance EIGRP neighbors. 349 OSPF. 183-184 maintaining neighbors.indb 887 LSU (Link-State Update) packets. 636 LSDB (link-state database). 183 exchanging with OSPF neighbors. 497 DiffServ DSCP values AF.marking 887 load balancing EIGRP. 452. 491 delay. 184-185 flooding. 497-499 with classification. 505-507 LSAs (link-state advertisements). 393 loopback interfaces. 47 STP impact. predicting. 440-441 log keyword. 491 Low Latency Queuing (LLQ). 721-724 location (ACLs). predicting. 49 forwarding. 283 logging IPv6 ACLs. 491 SNMP. 491 IPv6 ACLs. 491 loss. 180 contents. 432 MAC addresses burned-in. 157-158 logins (AAA). 150 Long-Term Evolution (LTE). 502-503 CS. 184-185 Managed Extensibility Framework (MEF). 111-112 instability. 764 managing bandwidth. finding. 184-185 LSAs relationship. 695 manual EtherChannels configuration. 685 jitter. 179 area design. 233 OSPF neighbors. 366 Management Information Base. unsolicited. 201 exchanging between neighbors DRs on Ethernet links. 670 log messages. 190 best routes. 263-264. 185-186 fully exchanging LSAs. See MIB management plane (networking devices). 502 6/1/16 12:04 PM . 393 M mac-address command. 503 EF. 651-652 HSRP. 44 loss. preventing. configuring. 147. 183-184 DRs on Ethernet links. 636 9781587205798_BOOK. 627 local SPAN. managing. 553 MLPPP.

696 STP Hello BPDU. 445-446 subset of address. 247. 342 debug. filtering. 62 Set RO/RW communities. 463-464 TCP and UDP port numbers. 310 DV routing protocols. 222. 218. See MTU measuring cloud computing services. 610. 699 SNMPv2 support. 699-701 writing variables on agents. 263 OSPFv3. 696-697 SNMPv2.indb 888 EIGRP. 446-447 wildcard masks. 739 end-user traffic. 56 maximum-paths command. 49 Trap. 710-711 NA (neighbor advertisement). 235-236 6/1/16 12:04 PM . 303. 446-448 MaxAge timer (STP). 229-230 EIGRP. 701-702 SNMPv3. 161 MEF (Managed Extensibility Framework). monitoring.1Q headers. 674 filtering.11 headers. 647 for IPv6. 643 maximum transmission unit. 441-442 matching parameters extended numbered ACLs protocol. 464-467 standard numbered ACLs any/all addresses. 261 9781587205798_BOOK. 501 IP headers. 445 exact IP address. 766 messages challenge. source IP. 651. 696 RO/RW communities. 500-501 Ethernet 802. 501-502 matching packets. 710-711 unsolicited log. 696-697 SNMPv2. 242 Get agent information. 699-701 ICMPv6 Echo request. 366 memory (TCAM). 501 trust boundaries. 499-501 MPLS Label headers. 283 update BGP. 232 RA (router advertisement). 668-669 NDP. 662 load balancing. 610. 699 SNMPv2 support. and destination IP. 713 MEC (Multichassis EtherChannel).888 marking Ethernet 802. 696 SNMP variables. 683 OSPF Hello. 679-684 Inform. 448 command syntax. 684 RS (router solicitation). 627. 181-182 partial update. 684 RSTP. 683 NS (neighbor solicitation). 270 EIGRP for IPv4. 701-702 SNMPv3.

231 IPv6 routes EIGRP for IPv6.indb 889 889 Layer 3 design. 721. 370-371 E-Tree service. controlling. 78-79 root. 366 E-LAN. 366 physical design. 626 OSPF. 362-364 access links. 74 port. 349-350 Layer 2 fragmentation balance. 696 MPBGP (Multiprotocol BGP). 568-569 mismatched masks. 240-241 route load balancing. 286 MLPPP (multilink PPP). 365-366 services. 368 hub and spoke. 368-372 E-Line. 265 EIGRP topology database. 697 variables monitoring. 348 configuring. 348-349 load balancing. troubleshooting. 728 monitoring MIB variables. 638-640 per-VLAN STP. 367-368 MIB (Management Information Base). 216-217 higher reference bandwidth. 367-371 E-Tree. 238-239 IGP. 351-353 monitor session command. 175-176 infinity. 236-237 components. 264 serial link bandwidth. 372 MEF. reviewing. troubleshooting. 217 setting. charging for. 373 bandwidth used. 697 views. 217 OSPFv3. 696 numbering/names. 215 based on interface bandwidth. 569-571 mismatched subnets. 369 Point-to-Point. 262 delay settings.MPBGP (Multiprotocol BGP) metrics BGP best path selection. 650-651 OSPFv3 interface costs. 366 9781587205798_BOOK. 265 calculation. 48 STP port. 305-306 EIGRP. 371-372 E-Line service. 795 mismatched IPv4 settings. 695-697 OIDs. 237-238 FD (feasible distance). 380 6/1/16 12:04 PM . 53 MetroE (Metro Ethernet). 349 Layer 3. 370 E-LAN service. 369 partial mesh. 369-372 topologies full mesh. 349 verifying. 240-241 RD (reported distance). 373-374 overages. 236 bandwidth. 365 data usage. 262 example. 705 mind maps. 374-375 IEEE Ethernet standards.

306 multilayer switches. 25. 501 Layer 3 design. 347 Multiple Spanning Tree (MST). 615 6/1/16 12:04 PM . 471-472 named mode (EIGRP configuration). 206-210 network commands. 118 router configuration. 768-770 NCP (Network Control Protocols). 249 names (MIB variables). 525-526 NBAR (Network Based Application Recognition). 697 National Institute of Standards and Technology (NIST). 679-683 implicit filtering messages through IPv6 ACLs. 135 named ACLs configuration. 47 multiple queues (queuing systems). 377 public cloud connections. 597 ndp –an command. 739 native VLANs. 432 multiarea on ABR OSPFv3 configuration. 20 mismatched on trunks. 40. 734 N NA (neighbor advertisement) messages. See MPLS VPNs MPLS VPNs (MPLS Virtual Private Networks). 375-377 access links. 341 NDA (nondisclosure agreement). 683 name command. 625 multiarea OSPFv2 configuration. 72 MTU (maximum transmission unit). 382 Layer 3. 207-208 subnets. 210-212 multiarea OSPFv3 configuration. 472 editing. See MPLS multithreading. 349 multiple frame transmissions. See Layer 3. 206 verifying. 161 multihomed Internet edge design. 498 NBIs (Northbound Interfaces). 296 mtu command. 682 Multichassis EtherChannel (MEC). 378 Label headers. 381-382 MST (Multiple Spanning Tree). 72 Multiprotocol BGP (MPBGP). 209 single-area configurations. 788 NDP (Neighbor Discovery Protocol). 593 filtering messages through IPv6 ACLs. 380 Multiprotocol Label Switching. 683-684 SLAAC. 378-379 virtual private networks. 376 EIGRP challenges.indb 890 multiple serial links between routers. switches multilink interfaces. 636-638 OSPF mismatched settings. 379-382 OSPF area design. 747 QoS. 504 9781587205798_BOOK. 236 IPv6 mismatches. 362.890 MPLS (Multiprotocol Label Switching) MPLS (Multiprotocol Label Switching). 622 multicast addresses. 473-475 overview.

341 network functions virtualization (NFV).Network Interface Modules (NIMs) 891 neighbor commands. 234 requirements. 181-182 LSDB exchange. 632-633 relationships. 648 for IPv6 compatibility. 315-318 static discard routes. 632 requirements. 285-286 EIGRP for IPv6. 293-294 Hello messages. 234-235 discovery. 313 eBGP configuring. 186. 318 classful network routes. 303 disabling. 735 Network Interface Modules (NIMs). 290-291 duplicate RIDs. injecting. 246 for IPv4. 312 disabling. 683 states. 633-635 verifying. 288 troubleshooting. 656-657 OSPF area mismatches. 683 BGP. confirming. 754 network interface cards (NICs). 218 multiarea configuration. 288-294 9781587205798_BOOK. 656 troubleshooting. 332 6/1/16 12:04 PM . 289 RIDs. 311 verifying. 323 BGP table entries. 285 routing protocol relationships. 270 enabling. 182-183. 274 solicitation (NS) messages. 286-290 verifying. 198-200 OSPFv2 interface configuration. 209 Network Control Protocols (NCP). 314 using link addresses. 181 requirements. 628 netsh interface ipv6show neighbors command. 314 neighbors advertisement (NA) messages. 718.indb 891 OSPFv3. 248 OSPF single-area configuration. troubleshooting. 181 states. finding. 314 states. 322 neighbor shutdown command. 312-313 EIGRP for IPv4. learning. 222. 284 pinging routers. 498 network command. 633-634 troubleshooting. exchanging. configuring. 656-657 requirements. 291-293 Hello/dead timer mismatches. 319-320 EIGRP. 253 topology information. 284 neighbor requirements. 183-186 meeting. 235. 647 wildcard masks. 286 status. 615 Network Based Application Recognition (NBAR). 314 advertising subnets to ISPs. 235-236 troubleshooting.

493 physical data center. 547-548 traffic bandwidth. 303 Network Management Station. 491 jitter. 315-318 contiguous. 267 discontiguous classful. 766 Northbound Interfaces (NBIs). 757 DNS services. 773-774 comparisons. 776 9781587205798_BOOK. 735 NIMs (Network Interface Modules). 766-767 defined. 491 loss. 332 NIST (National Institute of Standards and Technology). See NMS Network Time Protocol (NTP). 491 types. 756-757 DHCP services. enabling. 267 controllers centralized control. 760 APIC Enterprise Module (APIC-EM). 757-758 networks analyzers. 754 NHRP (Next Hop Resolution Protocol). 764 security. 696-697 no auto-summary command. 736 programmability. 754 VMs. 701 SNMP. See authentication. 768-770 Southbound Interfaces (SBIs). 695 notification community strings. 762 control. 762-763 management plane.892 Network Layer Reachability Information (NLRI) Network Layer Reachability Information (NLRI). 774-776 Application Centric Infrastructure (ACI). 736 Nexus 1000v vSwitch. 412-413 dynamic mapping.indb 892 public cloud address assignment services. 400-401 virtual. 491 characteristics. 735-736. 268 6/1/16 12:04 PM . centralizing. injecting. 492-494 unsecured. 719 broad access. 718. 303 NMS (Network Management Station). 763-764 data plane. 752-754 redundancy needs. 739 classful autosummarization at boundaries. AAA servers switch internal processing. 412 spoke-to-spoke communication. 266-267 routes. 736 NFV (network functions virtualization). 491 delay. 754-756 NTP. 757-758 VNFs. 766-767 control plane. 739 NLRI (Network Layer Reachability Information). 767-768 devices. 266-268 flow. managing. 413 NICs (network interface cards). 765-766 discontiguous.

788 noninteractive data application traffic. 493 nonroot switches (RPs). 808 O ODL (OpenDaylight). 270 no shutdown command. 650. 189-190 backbone areas. troubleshooting. 189 ABR. 543 routed ports. 771 operations (IP SLAs).indb 893 numbered ACLs. 572 no ip sla schedule 1 command. 772 Open Shortest Path First. 771-772 OpenFlow.OSPF (Open Shortest Path First) 893 no ip access-group command. 710-711 NS (neighbor solicitation) messages. 535 nondisclosure agreement (NDA). 359 EIGRP for IPv6. 40. editing ACLs with. 713-715 OpFlex. 475-476 numbers AS numbers. 190. 294 ROAS subinterfaces. 354 OSPF processes. 715 no neighbor shutdown command. 95 no spanning-tree portfast default command. 473-475 numeric reference table conversions binary-to-hexadecimal. 555 MIB variables. 785 Northbound Interfaces (NBIs). 757-758 9781587205798_BOOK. 170. 799 OIDs (object IDs). 527 no spanning-tree portfast bpduguard default command. 768. 768 OSC (Open SDN Controller). 805-807 hexadecimal-to-binary. 179 area design. 210-211 areas. 771 Open SDN. 223. 539 Layer 3 switches. 697 ROAS subinterfaces. 701 notifications SNMP. 662 Layer 1 leased-line WAN problems. 476 no ip address command. See ASNs HSRP group. 491 ONF (Open Networking Foundation). 768-770 notification community strings. 808 decimal-to-binary. 683 NTP (Network Time Protocol). 539 no ip domain-lookup command. 103 tiebreakers. 696-697 SNMPv3. 739 one-way delay. See OSPF OpenDaylight (ODL). 95 no switchport command Layer 3 EtherChannels. 697 on-demand self-service (cloud computing). 525 sequence. 771-772 Odom. 190 backbone routers. 102-103 normal-time questions. 314 no passive-interface command. 190 6/1/16 12:04 PM . Wendell Twitter/Facebook information. 101-103 problems. 772 OSPF (Open Shortest Path First). 771 Open SDN Controller (OSC). configuring.

191 interarea routes. 217 LSAs. 294-296 RIDs configuring. 215 based on interface bandwidth. 184-185 meeting. 213-215 Dijkstra SPF algorithm. 217 metrics.indb 894 area mismatches. 293-294 LSAs. 219-221 load balancing. 291-293 Hello messages. 284. 180 EIGRP. 289 RIDs.894 OSPF (Open Shortest Path First) benefits. 296 neighbors. 216-217 EIGRP interfaces. reducing. 619 interarea routes. 215 based on interface bandwidth. 281-283 load balancing. 183-184 maintaining. 196 troubleshooting. 181 requirements. 381 Version 2. 290-291 DRs on Ethernet links. verifying. 217 MTU mismatched settings. compared. 203-204 duplicate. 282-283 mode. 213-215 dual stack. calculating. 189 problems. shutting down. 181 9781587205798_BOOK. 189 best routes with SPF. 170 default routes. 619 interface configuration example. troubleshooting. 217 setting. 190 three-area. 181 states. 288-294 process-ids. 198 processes. 182-186. 188. 281 identifying. finding. 190 MPLS VPNs. learning. 293-294 history. 217 6/1/16 12:04 PM . troubleshooting. 190 internal routers. 181-182 Hello/dead timer mismatches. 212 interfaces costs. setting. 190 intra-area routes. 218 verifying. 188 SPF workload. 216-217 higher reference bandwidth. 198 default routes. 217 setting. 185-186 duplicate RIDs. exchanging. 281 single-area. 291-293 super backbone. 275 passive. 186-188 configuration errors. 302 Hello/dead timers. 216-217 higher reference bandwidth. compared. enabling. 179 metrics. 619 history. 381-382 network size. 224 goals. 288 troubleshooting. See OSPFv2 OSPFv2 (OSPF Version 2).

621. 620 configuration. 623-624 dual stack. 196-197 passive interfaces. 743-744 packets classification. 583-585 without VLSM. 374-375 overlapping routes. 206 verifying. 498 router queuing. 233 single-area configuration. 496 routers. 504 output queuing. 628-629 RIPv2/EIGRP. 636 LSDBs. 203-204 verifying. 496-497 NBAR. 210-212 OSPFv3. 504 overages (MetroE data usage). 497 matching. 636 neighbors. 197 matching with network command. 497 with marking. 633-635 verifying. 627 multiarea example. 636-638 routes. 512 TCP windowing. 626 single-area.packets 895 multiarea configuration. 625 route selection metrics. 197-198 IPv4 addresses. 630-631 IPv6 MTU mismatches. 621. 633-634 troubleshooting. 200-202 wildcard masks. 581-583 P PaaS (Platform as a Service).indb 895 LSAs. 638-641 9781587205798_BOOK. 632-633 OSPFv2. 199 OSPFv3 (OSPF Version 3). 627-628 load balancing. 630 troubleshooting. 624 RIDs. compared. 619 interfaces. 206-210 network commands. 616 address families dual stack. 207-208 subnets. compared. troubleshooting. 631-632 verifying. 513-514 congestion management. 628-629 passive interfaces. 504 6/1/16 12:04 PM . 505-507 multiple queues. 198 organization. 512-513 tools. 577-580 overlapping subnets with VLSM. 632 requirements. 209 single-area configurations. 204-206 RIDs. 207-208 network command. setting. 504 Low Latency Queuing (LLQ). 624 output queuing. compared. 621 default routes. 198-200 multiarea configurations. 622 multiarea on ABR. 497 congestion avoidance. 495 ACLs.

675 PAgP (Port Aggregation Protocol). 698 path attributes (BGP). 512 slowing messages. 297 EIGRP. 509 edge between networks. 624 Password Authentication Protocol. 86 9781587205798_BOOK. configuring. 198 wildcard_mask. 507 round robin scheduling. 778 APIC-EM Path Trace app. 495 filtering. 510 traffic rate versus configured policing rate. 503 DiffServ DSCP EF values. 305-306 Path MTU Discovery (PMTUD). 624 passive-interface default command. 507 discarding excess traffic. 222. 502 IP headers. 510 time intervals.indb 896 PAP (Password Authentication Protocol) authentication. 232. 346-347 parameters ICMPv6. 196. 500 PE (provider edge). 505 de-encapsulating/re-encapsulating with HDLC. 502-503 DiffServ DSCP CS values. 398 shaping.1Q header). 343.896 packets prioritization. 198 partial mesh topology (MetroE).11 headers. 270 passive interfaces EIGRP. 336 defined. 196 OSPFv3. 205 defined. 235 passive-interface command. 34 PCP (Priority Code Point) field (802. 669 ip_address. 675 marking. 499 802. 508 router originated. 505 queuing strategy.1Q headers. See ACLs ICMPv6. 377 6/1/16 12:04 PM . 270 OSPF interfaces as passive. 668 paths forwarding APIC-EM Path Trace ACL Analysis tool. 497 DiffServ DSCP AF values. 501-502 matching. 777 selections. 441-442 policing. 500-501 802. 251 OSPF. 670 router queuing. 251. 356 configuring. 511-512 TCP. 509-510 features. 172 PBX (private branch exchange). 499-501 MPLS Label headers. 507. 496 routing over serial links. 369 partial updates (EIGRP). 501 with classification. 510 features. See PAP passwords. 205. 501 trust boundaries. 675 UDP. 204-206 OSPFv3.

229 permit command. 410 IPv6 ACLs. 93 point-to-point GRE tunnels. 365-366 physical server model. 333-334 troubleshooting. 63. 432 permit icmp any any routeradvertisement command. 743-744 PMTUD (Path MTU Discovery). 448-449 Per-VLAN Spanning Tree Plus (PVST+). 93 Point-to-Point Protocol. 341 framing. 615 IPv6 connectivity. 330-331 building. 614 leased-line WANs. 353 self-ping. 606-607 name resolution problems. 334 with HDLC. 129 Platform as a Service (PaaS). 762-763 management. 605-606 planes (networking devices) control. 63. 354 Layer 2 problems.Point-to-Point Protocol 897 Pearson Network Simulator (the Sim). 336 framing. 341 multilink. 332-333 with PPP authentication.indb 897 planning EIGRP configuration. 343-344 configuring PPP CHAP. 571-574. 336 configuring HDLC. 346-347 control protocols. 600-602 routes. 684 permit icmp any any router-solicitation command. See PPP 6/1/16 12:04 PM . 615 IPv6 ACLs. 607-608 working only in some cases. 675 GRE tunnel ACLs. 399 point-to-point lines. 483-485 ping6 command. 763-764 data. 487 extended IPv6 ACLs. 471-474. 344-346 configuring PPP PAP. 764 9781587205798_BOOK. 337-340 de-encapsulating/ re-encapsulating IP packets. 672 permit gre command. testing. 357-358 mismatched subnets. 684 permit ipv6 commands. 734 ping command. 335-336 CSU/DSU. 736 physical design (MetroE). 353-354 Layer 1 problems. 72-73 physical data center networks. 796 peers (BGPs). 483. 354-356 Layer 3 problems. 668 point-to-point edge ports. 303 periodic updates. 246 VTP configuration. 358 Point-to-Point over Ethernet. 674 IPv6 connectivity. 687 permit keyword. 442. 601 pings (IPv6 hosts) failure from default router. 342-343 configuring PPP. See PPPoE point-to-point ports. testing. 340 speeds. 336 physical components. testing. See MLPPP PPP functions.

62-63 roles. 52-53 trusted/untrusted. 344-345 verifying. 304.898 Point-to-Point topology (MetroE) Point-to-Point topology (MetroE). 49. 86 costs IEEE default. 343-344 control protocols. 413 authentication. 92 SPAN destination/source. choosing. 810 PPP (Point-to-Point Protocol). 54. 340. 60 Layer 3 switch routed. 60. 340 multilink (MLPPP). choosing. 154 powers of 2 numeric reference table. 82-83 ports 802. displaying. 62 switch root. 60 alternate. 101-103 switches. See EtherChannels PortFast. 345-346 configuring. 304. 374 QoS. 60 disabled. 92 STP versus RSTP. 349-350 Layer 2 fragmentation balance. 81 enabling/disabling. 91-92 backup. 60. matching. 53. 349 Layer 3. 342-343 CHAP authentication. 151-153 configuring.indb 898 per-VLAN STP costs. 510 traffic rate versus configured policing rate. 464-467 9781587205798_BOOK. 341 leased-line WANs. 365 Port Aggregation Protocol (PAgP). 52-53 RSTP backup. 719 stacking ports. 156 states RSTP. 78-79 designated. 534-537 numbers. choosing. 342. 83 verifying. 414 framing. 356 configuring. 92-93 types. 509 edge between networks. 773 filtering. 739 PoP (points of presence). 63. 508 rate. 86 PortChannels. 91-92 states. 60 nonroot switches. 367-368 points of presence (PoP). 153 DHCP snooping. 60-61. 91-92 blocking. 65 configuring. 341 dial connections to ISPs. 509-510 features. 668 policing data overages (MetroE). 365 policies ACI. 348 configuring. 508 pooling resources. 507 discarding excess traffic. 44 channels. 55 STP.1w RSTP roles. 74 root (RPs). 83 global settings. 348-349 6/1/16 12:04 PM .

670 preparing for the exam CLI skills. 790 checklist. 786-787 preparing for failure. 557-558 pre-exam suggestions. 425 session status. 790 knowledge gaps. 432 ppp chap password command. finding. 429 summary. 789-790 pre-exam suggestions. 421-422 Layer 3 status. 790-791 CCNA R&S. 417 Layer 3. 349. 790 ICND2. 427-428 Layer 2. 432 pppoe enable command. 790 other. 356 configuring. 792-793 practice exams answering questions. 417-418 summary. 792 scores. 427 Layer 1. 417. 790 checklist. 788 6/1/16 12:04 PM . 417 status.indb 899 899 verification. 424 virtual-access interfaces. 350. 420-421 dialers. 360 ppp multilink group 1 command. 414 troubleshooting. 359 ppp chap hostname command. 796-797 taking. finding. 413-415 configuring. 789-790 preemption (HSRP active/standby roles). 344 ppp authentication chap command. 417 history.preparing for the exam load balancing. 415-416 ISP router configuration example. 790 ICND2. 786-787 prefixes BGP. 346. 343. 419 Layer 1. 792-793 other. 430 9781587205798_BOOK. 426 dialer 2 status. 787 knowledge gaps. 425-426 customer router configuration. 359 PPPoE (Point-to-Point over Ethernet). 423 pppoe-client dial-pool number command. 416-417 Layer 2. 346-347 PPPoE Layer 2 configuration. 432 practice exams answering questions. 432 ppp multilink command. 350 ppp pap sent-username command. 794-796 exam-day suggestions. 418-419 enabling. 428-429 Layer 3. 594. 345 ppp authentication command. 303 IPv6. 417. 351-353 PAP authentication. 349 verifying. 790-791 CCNA R&S. 792 scores. 796-797 taking. 360 ppp multilink group command.

49 6/1/16 12:04 PM . 751 types. 303 table entries. 373-375 E-LAN services. 365 data usage. 198 processes OSPF. 774-776 Application Centric Infrastructure (ACI). 713-715 process-ids (OSPF). 302 internal (iBGP). 378-379 VPNs. 304 ASNs. 300. 776 proprietary routing protocols. 368-372 E-Line services. 320-321 neighbors. 364 access links. 62 programmability (network). 784-785 prioritization (congestion management). 310 external. 376 9781587205798_BOOK. 303. 366 partial mesh topology. 369 physical design. 305-306 configuring. 369 IEEE Ethernet standards. 365-366 Point-to-Point topology.1Q header). 294-296 RSTP. 366 MPLS. 378 Layer 3 design. 370-372 MEF. 303-310 BPDUs (bridge protocol data units). 797-798 tutorial. 224 BGP. 34 private cloud computing. 760 APIC Enterprise Module (APIC-EM). 797 study tasks. 304 best path selection. shutting down. 746-749 branch office connections. 367-371 E-Tree services. 377 MPLS VPNs. injecting. 303 AS. 367-368 services. 174. 303 reachability. 368 hub and spoke topology.indb 900 public cloud accessing. 366 Layer 3 design. 500 priority queues.900 preparing for the exam question types. learning. 506 priv keyword (snmp-server group command). 313-314 prefixes. 505 Priority Code Point (PCP) field (802. See eBGP IGPs. 707 private branch exchange (PBX). 375-377 access links. 314-320 update messages. 362 probes. 175 protocols. 798 studying after failing to pass. 302 route advertising. compared. 784 ready to pass assessment. 303-304 routing table analysis reports website. 304 ISP default routes. 369-372 full mesh topology. 739-741 private WANs MetroE. 773-774 comparisons. 379-382 QoS.

173. 180 DTP. 555 9781587205798_BOOK. 228 distance/vector information learned. 342. 306-309 neighbors. 175 subnets. 550-551 GLBP.protocols 901 CHAP authentication. 303 IGRP. 231-232 split horizon. 549 options. 413 NTP. 757-758 6/1/16 12:04 PM . 683-684 SLAAC. See HSRP need for. See IPv4 routing IPv6. 764 DHCP Binding Table. 304 Internet edge. 175 management plane. 557 configuring. 304 IGPs. enabling. 175 FHRP. choosing. 151-154 Dijkstra SPF algorithm. 597 NHRP. 553 no preemption. 550 HSRP. 765 matching. 153 DHCP Relay. 552 group numbers. 559-560 iBGP. 560-563 verifying. 146 eBGP. 463-464 MPBGP. 232-233 route poisoning. 551 active/standby routers. 336-340. 177 configuring. 229-230 EAP. 398 HSRP. 116 DV (distance vector). 302 metrics. 331. 356 configuring. 551 active/passive model.indb 901 active/standby rules. 175-176 routing protocol algorithm. 302 classless/classful. compared. 345-346 control plane. 554 failover. 544 HDLC. 175. 573 public cloud services. 311-314 EGP. 173. 555-556 versions. 544 features. 380 NDP. 558 troubleshooting. 146 EAPoL. 230-231 update messages. 679-683 implicit filtering messages through IPv6 ACLs. 310 goals. 412-413 dynamic mapping. 302 EIGRP. 593 filtering messages through IPv6 ACLs. 555 load balancing. 344-345 verifying. 544. 226 BGPs. 175 IPv4. 757 snooping. 412 spoke-to-spoke communication. 228 EIGRP as. 557 with preemption. See IPv6 routing link-state.

413. 226 route redistribution. 226 RIPv2. 62. 177-178 algorithms. 310 windowing. 302 EIGRP/OSPFv2. 425-430 verification.indb 902 interfaces enabled with. See OSPFv3 PAgP. 88 link types. 175-176. 419 troubleshooting. 173 defined. 233 IPv4. 172-173 IGP. 266-268 classless/classful. See DV protocols EGP (exterior gateway protocol). 274 interior comparison.902 protocols OSPF. 91-92 port states. 173 functions. 175 AS. 175 RIPv1. 58 STP. 86 PAP authentication. See OSPF OSPFv2. 146-148 RIP. 63 port roles. 512-513 6/1/16 12:04 PM . 172 routed. 464-467 transporting messages between BGP peers. 346-347 PPP. 415 configuring. 60. 59-60 RTP. 266 convergence. 148 TCP BGP connections. 343. 235 SNMP. compared. 174 autosummarization. 62-63 Cisco Catalyst STP modes. 414 ISP router configuration example. 233 goals. 62 standards. 273-274 RSTP alternate ports. 226 RIPv2. 92 processes. 92-93 port types. 177 troubleshooting. 173-177 9781587205798_BOOK. 172 routing administrative distance. See STP TACACS+. compared. See OSPFv2 OSPFv3. 172 proprietary. verifying. 420-425 RADIUS. 63. 415-419 enabling. 88-90 implementing. 417 history. 302 routable. 48 STP. 177. 60-61 backup port role. 356 configuring. 675 port numbers. 175 path selections. See PPP PPPoE. 202 link-state. displaying. See SNMP STA (spanning-tree algorithm). 313 packets. 172 DV. matching.

746-749 VPNs. 488 bandwidth. 129-131 domains. 127-128 public cloud computing. 131-133 synchronization. 505-507 multiple queues. 504 output queuing. matching. 748-749 NTP. 751 private WAN connections. 757-758 VNFs. 488 delay. 128 planning configuration. 464-467 VRRP. 504 prioritization. 745-746 private WANs. 751 9781587205798_BOOK. 492 QoS (Quality of Service). 754-756 intercloud exchanges. 747 address assignment services. 135-139 versions. 125-126 transparent mode. 496-497 NBAR. 757 DNS services. 120 configuration. 497 with marking. 491 jitter. 123 provider edge (PE). 512-513 tools.indb 903 DHCP services. 127 VLAN support. 129 pruning. 749-752 email services traffic flow. 756-757 branch offices example. 135 troubleshooting. 496 routers. 72-73 Q QoE (Quality of Experience). 497 congestion avoidance. 491 6/1/16 12:04 PM . 491 loss. 123 storing configuration.QoS (Quality of Service) 903 UDP Jitter probes. 544 VTP. 713 packets. 495 ACLs. 507 round robin scheduling. 126-127 servers. IPv6 ACL matching. 124 standard range VLANs. 134-135 switches synchronization to VLAN database. 378. 498 router queuing. 497 matching. verifying. 377 pruning (VTP). 512 TCP windowing. 125-127 features. 504 Low Latency Queuing (LLQ). 505 defined. 120 automated update powers. 505 queuing strategy. 127-128 requirements. adding. 675 port numbers. 491 classification. 752-754 PVST+ (Per-VLAN Spanning Tree Plus). 750-751 Internet connections. 741 accessing with Internet. 513-514 congestion management.

See RSTP rate limiting (DHCP snooping). 504 Low Latency Queuing (LLQ). 495 tools. 797 Real-time Transport Protocol (RTP). 507. 378-379 needs based on traffic types data applications. 510 features. 790-791 budgeting time. 699 read-write (RW) communities (SNMP). 492-493 video applications. 610. 501-502 MPLS. 506 routers. 784 9781587205798_BOOK. 502 Ethernet 802. 511-512 switches/routers. 499 with classification. 508 shaping. 739 Rapid PVST+. 507 priority queues. 510 traffic rate versus configured policing rate. 146-148 rapid elasticity (cloud computing). 496 R RA (Router Advertisement). 501 IP headers. 235 redistribution Internet edge ISP routes. 550 HSRP. finding. 505 round robin scheduling. 302 read-only (RO) communities (SNMP). 494 voice applications.11 headers. 509 edge between networks. 505-507 multiple queues. 505 strategy. 785 knowledge gaps. 496 VoIP. learning. 684 RADIUS protocol. 504 prioritization. 501 trust boundaries. 72 Rapid Spanning Tree Protocol. 507 discarding excess traffic. 512 slowing messages. 502-503 DiffServ DSCP CS values. 504 output queuing. 497 DiffServ DSCP AF values. 242 questions (exam) answering. 503 DiffServ DSCP EF values. See HSRP 6/1/16 12:04 PM . 154 RD (reported distance). 699 ready to pass assessment (exam).904 QoS (Quality of Service) marking. 493-494 query messages (EIGRP). 499-501 MPLS Label headers.indb 904 queuing congestion management. 510 time intervals. 792-793 types. 509-510 features. 240-241. 500-501 Ethernet 802. 380 redundancy FHRP features. 506 queue starvation. classification for.1Q headers. 257 reachability (BGP). 493-494 policing. 309 routes (MPLS VPNs).

524 configuration. 550-551 LANs problems caused without STP. 284 EIGRP. 596 Reliable Transport Protocol (RTP). 181 configuring. troubleshooting. 704 VTP. 233 goals. 528-529 verifying. 257 Representational State Transfer (REST). 628 relay agents (DHCPv6). 769 9781587205798_BOOK. 395 RIDs (router IDs). creating. 487 Remote SPAN (RSPAN). 769 reverse engineering from ACL to address range. 633-634 SNMPv3 configuration. 242 reported distance (RD). 699 ROAS (router-on-a-stick). 549 options. 252 OSPF. 721 reply messages (EIGRP). 45-46 STP. 525 subinterfaces. 527 roles ports alternate. 524 native VLANs. 769 requirements cloud computing services. confirming. 226 RIPv2 (RIP Version 2). 284 states. 62-63 6/1/16 12:04 PM .indb 905 RESTful APIs. 226 EIGRP/OSPFv2. 126-127 resource pooling (cloud computing). 526-527 connected routes. 694 RFC 4301 Security Architecture for the Internet Protocol. 42 network needs for. 526 show vlans command. 547-548 single points of failure. 289 OSPFv3. 235 remark command. 524 example. 624 RIP (Routing Information Protocol). troubleshooting. 284 EIGRP for IPv6. 472. troubleshooting. 216-217 relationships (neighbors). 713 REST (Representation State Transfer). 547 reference bandwidth. 175-176. 60-61 backup. 291-293 OSPFv3. 454-456 reversed source/destination IP address. configuring. 656 neighbors. 656-657 OSPFv3.roles 905 need for. 240-241. 480-481 RFC 1065. 739 responders (IP SLAs). 527 subinterface state. 302 RO (read-only) communities (SNMP). 196 EIGRP. 633-635 pinging routers. 203-204 duplicate. compared. 520. 524-525 troubleshooting. 525-526 subinterface numbers. 286 OSPF. 181 defining. 739 EIGRP for IPv6 neighbors. 285 requirements.

610 routers. 555 load balancing. 246. 190 interface OSPF areas. 172 Router Advertisement (RA) messages. 270. 555 active/standby rules. 557 configuring. configuring. 77 troubleshooting. 179 GRE tunnels between.indb 906 best routes. verification. 50 root costs (switches). 647 router-id command. 558 troubleshooting. 196 router-on-a-stick. 553 no preemption. verifying. routing ABR (Area Border Router). choosing. 60. 185 backup (BDRs). 643 RIDs. 185 discovering. 498 Cloud Services Routers (CSRs). 399 HSRP active/passive model.906 roles root. 80-81 ruling out switches. 99-101 round robin scheduling (queuing). 614 OSPFv3. 554 failover. 505 round-trip delay. 747 configuring different VIPs. 610. 684 router bgp command. 190 9781587205798_BOOK. 198 Router Solicitation (RS). 311 router eigrp command. 497 ACLs. 684 backbone. finding. 552 group numbers. 563 data plane processing. 190. 610. 91-92 STP. See RPs root switches electing. 172 routed ports. 623-624 IPv6 addressing configuration. See RPs RSTP. 222 router ospf 1 command. 185-186 DROthers. 180 classification. 211-212 Ethernet links. 551 active/standby routers. 100-101 STP. See also routes. 598 6/1/16 12:04 PM . 559-560 IDs. 222. 48 root ports. 601-603 issues. 557 with preemption. 210-211 OSPFv2 multiarea configuration. See ROAS router ospf command. 186 flooding. 598-599 connectivity. troubleshooting. verifying. 50-52 election influence. 497 NBAR. 209-210 advertisement (RA) messages. defining. 196. 763 designated (DRs). See RIDs internal. 534-537 routed protocols. enabling. 604 routing. 560-563 verifying. 715 routable protocols. 491 Round Trip Time (RTT). 624. 57 root bridge IDs. 555-556 versions.

525-526 subinterfaces. learning. 650-651 OSFPv3 metrics. 257-258 routing. 524 configuration. 524-526 native VLANs. 419 LSAs. 523 protocols. 305-306 classful networks. 242 feasible successor.routing 907 static route configuration. 231-232 redistribution. 234 load balancing. 640 IPv6 EIGRP for IPv6 metrics. 626. 357 interarea. 260-261 identifying. 599 troubleshooting. 23. 504-507 strategy. 320-321 Internet edge. 263-264 9781587205798_BOOK. 611-612 ISP. 573-574 DNS problems. 216-217 public cloud networks. 507 redundant. 213-215 interarea. 572 DHCP issues. 585 routing IP packets over serial links. 638-640 static. 259 variance. 303-304 best path selection. See routing protocols troubleshooting default router IP address setting. 640-641 ISP default. 319 EIGRP choosing. verifying. 241-242 convergence. 549. 309 OSPF default routes. 347 OSPF interface costs. 599 troubleshooting. 380 static discard. 319-320 successor. 754 QoS. 571-572 incorrect addressing plans. 526-527 router WAN interface status. 575-576 VLAN routing. creating. 21-23 routes. 258-260 host. routing BGP advertising. 610. 650 LANs. 684 troubleshooting DHCP issues.indb 907 tuning with bandwidth. 212 poisoning. 581-585 IP forwarding issues. 496 congestion management. 573-574 LAN issues. routes EIGRP for IPv6. 495 queuing classification for. 263-264 EIGRP for IPv6. configuring. 627-628 discard. 636 multiple serial links between. 528-529 verifying. See also routers. 315-318 default. 524-525 troubleshooting. 659-660 feasibility conditions. 577-580 6/1/16 12:04 PM . See also routers. learning. 398 solicitation (RS) messages. injecting. enabling/disabling. 177. See also FHRP ROAS.

88 link types. 274 internetwork. 202 link-state. 267-268 classless/classful. 63 ports roles. verifying. 575-576 mismatched IPv4 settings. 58-59 alternate ports. 62-63 Cisco Catalyst switch RSTP modes. 60. 172 DV. 715 6/1/16 12:04 PM . 266-267 discontiguous classful networks. 177 troubleshooting configuration errors. 684 RSPAN (Remote SPAN). 58 STP. 231-232 split horizon. 173 defined. 233 IPv4.indb 908 proprietary. 585 VLAN. 173 algorithms. 274 routing tables. 226 RIPv2. compared. 175 classless/classful. 92-93 types. 175 path selections. 266 convergence. 568-569 mismatched masks. 569-571 router WAN interface status. 173 functions. 91-92 states. 63. 175 AS. 266 classful network boundaries. 172 9781587205798_BOOK. 62 standards. 172-173 IGP. choosing. 102-103 switches. 235 RTT (Round Trip Time). 52-53 RS (Router Solicitation) messages. 226 route redistribution. 59-60 RTP (Real-time Transport Protocol). 174 autosummarization. troubleshooting. See VLAN routing Routing Information Protocol (RIP). 92 processes. 60-61 backup port role. 610. 177 metrics. 62. 177-178 algorithms. 273 neighbor relationships. 175-176 interfaces enabled with. 175 routing protocols administrative distance. 228 EIGRP as. 88-90 implementing. 235 RTP (Reliable Transport Protocol).908 routing LAN issues. 230-231 update messages. 229-230 EGP (exterior gateway protocol). 175. 175 RIPv1. 274 interior comparison. 228 distance/vector information learned. analyzing. 177. 60 nonroot switches. 721 RSTP (Rapid Spanning Tree Protocol). 273 RPs (root ports). 103 tiebreakers. 232-233 route poisoning. 101-103 problems.

configuring. 699. verifying. 146 username/password combinations. 145 EAP. 771-772 OpenFlow. 145 AAA servers. 148-150 login authentication rules. 771 Southbound Interfaces (SBIs). 771 Secure Shell (SSH). 770 comparisons. 767-768 scoring exams. 153 rate limiting. 396-397 9781587205798_BOOK. configuring. 707-708 IEEE 802. 153 features. 766-767 Northbound Interfaces (NBIs). 773-774 architecture. 699 S SaaS (Software as a Service). 148 909 rules AAA login authentication. 760 APIC Enterprise Module (APIC-EM).1x. 150 authentication 802. 144-146 AAA servers. 393 SNMPv3. 768-770 OpenDaylight SDN controller. 707-708 DHCP snooping configuration settings. 100-101 RW (read-write) communities (SNMP). 532 sdm prefer lanbase-routing command. 152 types. 147 TACACS+/RADIUS protocols. 393 IPsec encryption.indb 909 security AAA servers configuration. 151 ports as trusted. 796-797 sdm prefer command. 395-396 SNMP. 145 authentication process. 774-776 Application Centric Infrastructure (ACI). 698-699 SNMPv3. 776 controllers centralized control. 145 Internet VPNs. 557 implicit IPv6 ACL ICMPv6 message filtering. 150 login process. 767-768 Open SDN. 152 DHCP Binding Table. 683-684 ruling out switches. 771 Open SDN Controller (OSC). 699. 150 HSRP active/standby. 147-150 Internet VPNs. 543 SDN (Software Defined Networking). 153 DHCP-based attacks. 151-154 encryption. 765 Secure Sockets Layer (SSL). 705-707 STP. 145 attacks DHCP-based. 153 trusted/untrusted ports. 154 rules summary. 743 SBIs (Southbound Interfaces).1x. 772 OpenDaylight (ODL). 65-66 6/1/16 12:04 PM .

754-756 Internet as WAN. verifying. 749-752 intercloud exchanges. 732-733 defined. 369-372 public cloud accessing with Internet. 510 slowing messages. 332 serial links. 511-512 shaping data overages (MetroE). 734 virtualization. 699 SNMPv2 support. 124 service-level agreements (SLAs). 734 multithreading. 712 service providers (SPs). 720-721. 734-735 hosts. 149 enabling. 741 rapid elasticity. 699-701 writing variables on agents. 366 E-LAN. 149 username/passwords. 367-371 E-Tree. 743 DHCP. 734 networking. 756-757 branch offices example. 732 physical server model. 395 shared ports. 93 6/1/16 12:04 PM . 395 session status (PPPoE). 739 Platform as a Service (PaaS).1x. 746-749 accessing with VPNs. 50 sender’s root cost. 147-150 configuring for 802. 739 resource pooling. 740 Infrastructure as a Service (IaaS). 424 sessions (SPAN). 739-741 public. See leased-line WANs servers AAA authentication. 747 address assignment. 483-485 sender’s bridge IDs. 734 hypervisors. 734 VTP. 473-475 serial cables. 742 measured. 735-738 VMs. 757 DNS. 375 shared edge ports. 739 on-demand self-service. 507. 510 features. 696 shaping (QoS). 145 Cisco hardware. 512 rate. 739 requirements. 362 services cloud computing broad network access. 389 MetroE. 748-749 session keys.indb 910 private. 743-744 9781587205798_BOOK. 739 cloud services catalogs. 50 sequence numbers. 93 shared keys. 736 virtual data centers. 145 defining. 368-372 E-Line. 510 time intervals.910 self-ping self-ping. 63. 745-746 accessing with private WANs. 739 Software as a Service (SaaS). 725 Set messages RO/RW communities.

96. 487 show ip bgp command. 271. 423 show interfaces vlan command. 346 PPP status. 289 OSPFv3 interface bandwidth. 395 shorter VLAN configuration example.indb 911 show interfaces status command Layer 3 EtherChannels. 250. 286 multilink interfaces. 323 show ip eigrp interfaces command. 405. 352 show controllers serial command. See SPF algorithm show access-list command. 540 show interfaces command. 297 neighbor status. 640 PPP CHAP status. 86 show etherchannel command. 536 show interfaces description command. 543 show ip access-list command. 360 show etherchannel 1 summary command. 116-117 show interfaces tunnel command. 31-34. 539 routed ports. 536 show interfaces switchport command. 457. 107. 313. verifying. 271 show ip eigrp neighbors command. 135 show interfaces trunk command. 38. 41. 473 show access-lists command. 433 9781587205798_BOOK. 271. 352 OSPF interfaces. 487. 298. 345 PPP PAP. 253 neighbor verification checks. verifying. 28-29 Shortest Path First algorithm. 275 STP status. displaying. 543. 283 neighbors. 114-116. 576 show interfaces dialer command. 286 MLPPP. 275 EIGRP neighbor requirements. 474-476 show ip access-lists command. 41. 433 show interfaces virtual-access command. 37. 569 EIGRP neighbor requirements. verifying. 285 show ip eigrp topology all-links command. 457. 297 EIGRP-enabled interfaces. 68 show controllers command. 344 routed ports. 572 show commands IPv6 ip eigrp topology command 911 shared session keys. 479. 421. 360. 260 show ip eigrp topology command. 433 show interfaces virtual-access configuration command. 323 show ip bgp summary command. 271 feasible successor routes. 450. 673 routing protocol-enabled interfaces. 687 show arp command. 298. 32-34. 479. 250-251. 259 metrics. 262 6/1/16 12:04 PM . 450. 352 show ip eigrp interfaces detail command. 543 show etherchannel summary command.

troubleshooting. troubleshooting. 662 show ipv6 eigrp neighbors command. 297 show ip route ospf command. 323. 223 show ip ospf interface brief command. 254. troubleshooting. 214 show ip sla enhanced-history distribution-statistics command. 289 show ip ospf database command. displaying. 289 OSPF status on interfaces. 577-578 show ip route static command. 298 DRs/BDRs details. 254 IPv4 routes added by OSPF. 202 OSPF configuration errors. 457. 210 OSPF-enabled interfaces. 211 Hello/dead timer mismatches. 479 show ip ospf command. 577-580 administrative distance. 223. 289 OSPFv2 interface configuration. 223. 271. 220 passive interface. 271. 298 duplicate OSPF RIDs. 275 EIGRP neighbors. 450. 211 neighbors. 256 show ip interface brief command. 729 show ipv6 access-list command. 283 show ip interface command. 663 6/1/16 12:04 PM . 178 dialer interface Layer 3 orientation. 281 OSPFv2 interface configuration. 221 show ip ospf interface command. 219 show ip route command. 425 EIGRP-learned routes. 179. identifying. 297 EIGRP-enabled interfaces. 223. 291 OSPF neighbors. displaying. displaying. 201. 223. 687 show ipv6 eigrp interfaces command. 271. 543 show ip route eigrp command. 275 OSPF neighbors. 729 show ip sla statistics command. 298. 663 show ipv6 eigrp topology command. 717. 205. 663 show ipv6 eigrp topology | section command. 295 show ip ospf neighbor interface brief command. 352 OSPF interfaces. 360 GRE tunnels. 258 topology table. 729 show ip sla summary command. 282-283 OSPFv2 interface configuration. 404 multilink interfaces. 286. 210 OSPF neighbors. 677. 298 OSPF areas for ABR interfaces. 298 DRs/BDRs details. 223. troubleshooting. displaying. 654. 286 IPv4 routing protocols. 288 OSPF processes shutdown. listing. 253. 662 show ipv6 eigrp interfaces detail command. 295 9781587205798_BOOK. 201 routing tables. 293 OSPF areas for ABR interfaces. 251-252. 182.indb 912 show ip protocols command.912 show ip eigrp topology command successor routes. 206 show ip ospf neighbor command. 729 show ip sla history command. 223. 223.

643 show ipv6 ospf neighbor command. 75-77 show spanning-tree vlan 10 interface gigabitethernet0/2 state command. 643 show ipv6 ospf interface brief command. 729 show snmp location command. 643 show ipv6 ospf database command. 723 show monitor session command. 449. 114 show mac address-table dynamic command. 702. 663 show ipv6 route ospf command. 728 show snmp group command. 83. 630. 729 show spanning-tree bridge command. 640. 96 show spanning-tree vlan 10 bridge command. 360 9781587205798_BOOK. 663 show ipv6 routers command. 424. 614. 96 show spanning-tree interface command. 708. 77 show spanning-tree vlan 10 command. 709. 687 show ipv6 neighbors command. 643 show ipv6 protocols command. 92 show spanning-tree vlan command. 81 show spanning-tree summary tcp summary command 913 show ipv6 interface command. 313 show tcp summary command. 724. 728 show snmp contact command. 703. 82 show spanning-tree root command. 353. 556 show tcp brief command. 614. 81 show spanning-tree command. 654 OSPFv3 interfaces. 111 show monitor detail command. 729 show monitor session all command. 638. 360 show pppoe session command. 630 show ipv6 route command. 643 show ipv6 ospf interface command. 433 show running-config command. 702. 614. 135. 565 configuration. 729 show ppp all command. 640. 635. 643 show ipv6 route | section command. 603 show ipv6 route eigrp command. 729 show snmp community command. 729 show snmp host command. 96 show standby brief command. 724. 323 6/1/16 12:04 PM . 603 show ipv6 ospf command. 662 EIGRP for IPv6 interfaces. 473-475 show snmp command. 77. 614 IPv6 ACL ICMPv6 NDP message filtering. 630-631. 681 show mac address-table command. 663 IPv6 router connectivity. 643 EIGRP for IPv6. 643 EIGRP for IPv6.indb 913 show ppp multilink command. 636. 346-347. 560 status. 555-565 show standby command (HSRP). 96 show spanning-tree interface detail command. 681 IPv6 IPv4 replacement. 614. 728 show snmp user command.

650. 203-204 verifying. 597 NDP. 29. 114 show vlan command. 207-208 network command. 294 ROAS subinterfaces. 696-697 notifications. 26-29. 201-202 LSDB contents. 696 Trap messages. 699 security. 692 agents. 698-699 Get messages agent information. 699-701 writing variables on agents.indb 914 single-area OSPFv3 configuration. 141 show vlan id command. 695-696 clear-text passwords. 197 matching with network command. 41. 712 SLAAC (stateless address autoconfiguration) EUI-64. 198-200 multiarea configurations. 204-206 RIDs. 796 Simple Network Management Protocol. 543 show vtp password command. displaying. 359 EIGRP for IPv6. 294-296 signatures. 696-697. See SNMP single-area OSPF. 394-396 SLA (service level agreement). 698 communities. 699 SNMPv2 configuration. 27. 547 site-to-site VPNs. 699 read-write (RW) communities. 131. 701-702 managers. 753 SNMP (Simple Network Management Protocol). 527. 40. 609-610 SLBaaS (SLB as a service). 597 IPv6 settings. 306 single points of failure. 701-702 snmp-server command. 134. 699-701 history. 114. 141 show vtp status command. 699 SNMPv2 configuration. 135. 700 6/1/16 12:04 PM . 695 Inform messages. 201 wildcard masks. 695 MIB. 498 the Sim (Pearson Network Simulator). 196-197 passive interfaces. 188 single-area OSPFv2 configuration. 134. 200-202 IPv4 routing protocols. 527 shutdown vlan command. 597 troubleshooting. 623-624 single homed Internet edge design. 199 9781587205798_BOOK.914 show vlan brief command show vlan brief command. 41. 140 shutting down OSPF processes. 141 shutdown command. 354 OSPF processes. 696-697. 114 show vlan status command. 135 show vlans command. 198 organization. 698-699 Set messages RO/RW communities. 662 Layer 1 leased-line WAN problems. 696 RO/RW communities. 696-697 read-only (RO) communities. 197-198 IPv4 addresses.

88. 719 Encapsulated RSPAN (ERSPAN). 721 local. 743 9781587205798_BOOK. 701. 705 write views. 713 ports (SPAN). 706 Inform messages. 90 spanning-tree pathcost method long command. 727 snmp-server group command. 711-712 users. 72 spanning-tree mode pvst command. monitoring. 704 summary. 727 snmp-server contact command. 701-702 verifying. 727 snmp-server enable traps command. 699-701 Trap/Inform messages. 705 snmp-server host command. 725 Southbound Interfaces (SBIs). 705-707 notifications. 777 sources addresses. 699 SNMPv2c (Community-based SNMP Version 2).indb 915 Software Defined Networking. 95 spanning-tree mode command. 710-711 requirements. 725 traffic direction. 721 spanning-tree algorithm (STA). 406 IPs. matching. 48 spanning-tree bpduguard disable command. 719 SPAN. 727 snmp-server location command. 720-721 source ports. 725 VLANs. 75 spanning-tree commands. 727 snmp-server user command. See SDN solution apps. 707 verifying. 710. 95 spanning-tree bpduguard enable command. limiting. 719 Remote (RSPAN). 719 sources. 463-464 IP SLAs. 708-709 groups MIB views. 699 SNMPv3 configuring. 702-704 security. 55 6/1/16 12:04 PM . 767-768 SPAN (Switched Port Analyzer).spanning-tree pathcost method long command 915 snmp-server community command. 707-708 groups. 721-724 network analyzer needs for. 705 security levels. 722 destination ports. limiting. 705 security. 707-708 encryption. 704 authentication. 710-711 MIB views. 72. 699 Trap messages. 707 SNMPv2 configuring Get/Set messages. 81. 721 sessions. 95 spanning-tree mode mst command. 718 dependencies. 72 spanning-tree mode rapid-pvst command. 710-711 Software as a Service (SaaS). 95 spanning-tree bpguard enable command.

95 Spanning Tree Protocol. 452-453 wildcard masks binary wildcard masks. 103 spanning-tree vlan command. 422 SPs (service providers). 158 9781587205798_BOOK. 74 speed command. 596 stateless address autoconfiguration. 576 speeds LAN/WAN interfaces. 48-49 6/1/16 12:04 PM . 55-56 discarding. configuring. 230-231 spoofing. 446-447 standard range VLANs. 447-448 decimal wildcard masks. 564 standby HSRP routers. 95 spanning-tree portfast command. 396-397 STA (spanning-tree algorithm). 156 stacking ports. 157 standard ACLs.916 spanning-tree portfast bpduguard default command spanning-tree portfast bpduguard default command. 186-188 spinning up VMs. 452-453 verification. calculating. 180 Dijkstra SPF. 454-456 troubleshooting. 157 stacking cables. See SLAAC states change reactions (STP topology). 448 matching exact IP address. 559 stateful DHCP. 95 spanning-tree portfast disable command. 156 stacking modules. 671-674 standard numbered IPv4 ACLs. 564 standby version command. 95 spanning-tree portfast default command. 75. 157-158 stack masters. 448-452 list logic. 443 access-list command. 156 stacking switches access layer switches. troubleshooting. 57-58 criteria. 362 SSH (Secure Shell). 83. 742 split horizon (DV routing protocols). 445 configuration examples. 48 stack masters. 444-445 matching any/all addresses. 554. 156-157 benefits. 81. 180 OSPF best routes. 445-446 matching subset of address. 446-447 overview. 490 leased-line WANs. See STP spanning-tree vlan 10 port priority 112 command.indb 916 operating as single logical switch. 443 reverse engineering from ACL to address range. 123 standby 1 preempt command. 333-334 SPF (Shortest Path First) algorithm. 558 standby command. 83. 608-609 stateful DHCPv6. 155 chassis aggregation. 557 standby version 1 | 2 command. 159-161 FlexStack/FlexStack-Plus. 454 command syntax. 61 interfaces changing with STP. 765 SSL (Secure Sockets Layer).

72 9781587205798_BOOK. predicting. 57-58 LAN redundancy. 58 behind the scenes summary. 57 tunnel interfaces. 83 global settings. 50-52 system ID extensions. 58 neighbors BGP. 81 enabling/disabling. 74 PVST+. displaying. 44 MAC tables impact. 82-83 6/1/16 12:04 PM . 319-320 static routes (IPv6). 42-46 LAN segment DPs.indb 917 BIDs defined. 527 STP. changing. 424 STP verification. 54 looping frames. 72-73 system ID extensions. 49 root switch election. 47 learning. predicting. 49 BPDU Guard configuring. 81 enabling/disabling. 555 interface codes. 88-89 configuration. 48. 83 verifying.STP (Spanning Tree Protocol) 917 forwarding/blocking. 73-74 BPDUs (bridge protocol data units). 83 PPP. 111-112 troubleshooting. 116 static discard routes. 82-83 Cisco Catalyst switch STP modes. displaying. 83 global settings. 71 modes. 58 listening. 186. 73-74 convergence. 72 options. 105-106 EtherChannels. 64-65 configuring. 233. 288 OSPFv3. 632 relationships. 84-87 MAC tables impact. 345 PPP PAP. 92-93 STP versus RSTP. 106-109 forwarding or blocking criteria. 110 PortFast. 74-75 per-VLAN port costs. 182-183. 48-49 interface states. 344 PPP CHAP. 407 VLAN mismatched trunking operational.1D standard. 313 OSPF. 353 PortFast global settings. preventing. 83 EIGRP neighbors. 346 PPPoE Layer 3. 425 sessions. 599 status BPDU Guard global settings. 42 802. 628 ports RSTP. 65 configuring. 56 STP (Spanning Tree Protocol). choosing. verifying. 75-77 steady-state operation (STP). configuring. 253 HSRP. 62 ROAS subinterfaces. 83 verifying.

44 costs. 58-59 alternate ports. 100-101 RSTP (Rapid STP). 593-594 mismatched EIGRP neighbors. 60-61 backup port role. 50-52. 258-260 6/1/16 12:04 PM . 53. choosing. 260-261 identifying. 47-49 roles. 91-92 port states. 88-90 implementing. 80-81 root switch election.indb 918 studying after failing the exam. 63 port roles.918 STP (Spanning Tree Protocol) ports blocking. troubleshooting. 525 state. 62-63 Cisco Catalyst switch RSTP modes. 102-103 timers. 99-101 RPs on nonroot switches. 62 purpose. 798 subinterfaces defined. 527 subnet masks mismatched masks. 446-447 successors EIGRP identifying. 303 IPv6. 241-242 for IPv6. 286 leased-line WANs. 78-79 states. 92-93 port types. 92 processes. 63. 524 ROAS creating. 569-571 VLSM (variable length subnet masking) overlapping subnets. 88 link types. 105-106 DPs on LAN segments. 104-105 root switch election. 581-583 subset of IP address. 101-103 verification. 646 feasible convergence. configuring. 56-57 switch RPs. 257-258 for IPv4. 583-585 without VLSM. 62 standards. 75-77 9781587205798_BOOK. 65-66 STA (spanning-tree algorithm). 52-53 tiebreakers. compared. 206 overlapping subnets with VLSM. 57 root election influence. 797-798 studying for exam. verifying. 56-57 switch reactions to changes. 58 STP. matching. 59-60 security. 358 OSPFv2 multiarea configuration. 48 states. 318 IGPs. 56-57 topology influences. 55-56 troubleshooting convergence. 583-585 recognizing when VLSM is used. 524-525 numbers. choosing. 581 subnets advertising to ISPs.

48 electing. configuring. 77 troubleshooting. 159-161 Cisco Catalyst RSTP modes. 21 Layer 3. 158 6/1/16 12:04 PM . 101-103 PortFast. 539-540 9781587205798_BOOK. 160 high availability with chassis aggregation. 80-81 ruling out switches. 722 destination ports. 145 access layer. 721 limiting sources. 159-160 distribution design. 520. 765-766 Layer 2. 541 verifying. 99-101 RPs (root ports). 725 local. choosing. 721 stacking access layer switches. improving. 531 links. 725 VLANs. 50-52 election influence. 721-724 network analyzer needs. 21 with routed ports. 532-534 verifying. 529-531 troubleshooting. 52-53 SPAN. 155 chassis aggregation. 718 dependencies.indb 919 Layer 3 with SVIs configuring.switches 919 super backbone (OSPF). 159-161 FlexStack/FlexStack-Plus. See SPAN switches as 802. 537-539 troubleshooting. 100-101 STP verification. 160 distribution/core switches high availability. 495 root costs. 161 design. 88-90 STP modes. 719 traffic direction. 156-157 benefits. 721 sessions. 532-534 verifying. 719 Encapsulated RSPAN (ERSPAN). 65 QoS. 719 Remote (RSPAN). 88-89 core. 156-157 adding. 157-158 nonroot. monitoring. improving. 534-537 VLAN routing. 720-721 source ports. 531 Switched Port Analyzer. 23-24 Layer 3 EtherChannels configuring. 63 logical. 159 benefits. 381 superior Hello. 529 configuring. 137-139 chassis aggregation. 159-160 internal processing. 50 supplicants. 145 SVIs (switched virtual interfaces).1x authenticators. 529-531 troubleshooting. 159-160 switch stacking.

920 switches operating as single logical switch. 785 time-division multiplexing (TDM). 464 TCP/IP networks. 189 TID fields (QoS marking). 310 windowing.indb 920 T T1. 766 T-carrier systems. 36-38. 40 switchport mode dynamic auto command. 40. 765 ternary content-addressable memory (TCAM). 116. 30. 334 time (exam) budget versus number of questions. 464-467 transporting messages between BGP peers. 694 TDM (time-division multiplexing). 313 packets. 135 synchronizing switches. 677 connectivity hosts. 155 virtual (vSwitches). 334 telcos (telephone companies). 73-74 9781587205798_BOOK. 124 switchport access vlan command. 37-40. 116. 131-133 VTP. 30. 25. 735 voice switches. 601-603 three-area OSPF. 334 TACACS+. 32 switchport mode trunk command. 135 switchport command Layer 3 switches. 113. 28-29. 535 switchport mode access command. 333 TCP (Transmission Control Protocol) BGP connections. matching. 512-513 tcp keyword. 125-126. 600-601 routers. 40 switchport trunk native vlan command. 116 switchport mode dynamic desirable command. 785 checking. 37-38. 501 tiebreakers (STP). 34 as VTP servers. 131-133 ToR (Top of Rack). 139 switchport trunk allowed vlan command. See leased-line WANs T3. 41. verifying. 102-103 time burners. 25. 117 switchport trunk encapsulation command. 157-158 stack masters. 390 Telnet. 34. 28. 513 TCAM (ternary content-addressable memory). 40. 675 port numbers. 543 routed ports. 331. 148 tagging (VLAN). 30. 136-137 system ID extensions (BIDs). displaying. 157 synchronization to VLAN database. 736 traditional access switching. 524 switchport nonegotiate command. 118 switchport voice vlan command. 139 switchport mode command. 18-20 tail drops. 41. 786 6/1/16 12:04 PM . 766 testing IPv6 ACLs.

troubleshooting. 507-510 queuing strategy. 369 partial mesh. 255-257 feasible successor routes. troubleshooting. 509 edge between networks. 504-507 marking. 614 traceroute6 command. 512-514 congestion management. 257-258 EIGRP for IPv6. influences. 713 IPv6 ACLs. 736 ToS (Type of Service) field (IPv4). 262 successor routes. measuring. 491 end-user. 777 QoS ACLs. 507 delay. 184 Hello/dead mismatches. compared. 233 Hello messages. 574 GRE tunnels.traffic 921 time intervals (QoS shaping). 504 output queuing. 499 traceroute command. 509-510 6/1/16 12:04 PM . 652 EIGRP neighbors. 505 strategy. managing. 611 routes. identifying. 511-512 timers EIGRP for IPv6. 496 classification. managing. 504 Low Latency Queuing (LLQ). testing. 491 loss. 615 tracert command. 293-294 STP. 736 topologies EIGRP displaying. 507-512 Top of Rack (ToR) switches. 507 discarding excess traffic. 366 full mesh. 615 traditional access switching. 368 hub and spoke. 55-56 ToR (Top of Rack) switches. 670 jitter. 499-503 policing. 188 STP. 369 Point-to-Point. 495-498 congestion avoidance. 504 prioritization. 155 traffic bandwidth. testing. 406 IPv6 connectivity. 657-658 MetroE. 513-514 congestion management. 491 characteristics. 505 round robin scheduling. 367-368 9781587205798_BOOK. 507 shaping. 491 congestion avoidance. 600-602 network router problems. 491 policing. 505-507 multiple queues. 512 TCP windowing. 777-778 APIC-EM Path Trace app. 56-57 tools APIC-EM ACL Analysis. 258-261 metrics. 512-513 tools. 777 APIC-EM Path Trace ACL Analysis tool.indb 921 OSPF area design.

indb 922 EtherChannels. 510 time intervals. 286 example. 356 DPs on LAN segments. 105 EIGRP for IPv6 interfaces. 560-561 group number mismatches. 701-702 SNMPv3. 481-482 reversed source/destination IP address. 725 types data. 477 ACL behavior in network. 562 with IP SLA counters. 288 mismatched subnets. 406 ACLs. 717 IPv4 ACLs. 511-512 SPAN sessions. 507. 135 Trap messages. 500 Transmission Control Protocol. 512 slowing messages. 285-286 9781587205798_BOOK. 480-481 troubleshooting commands. 407 Layer 3 issues. 573-574 6/1/16 12:04 PM . 696-697 SNMPv2. 715-716 history data. 655 neighbors. 656-657 routes. 278-281 working details. 108-109 GRE tunnels. 409-410 interface state. 563 misconfiguration symptoms. 276-278 EIGRP neighbors authentication failures. 510 features. 508 public cloud branch office email services. 479-480 IPv4 routing default router IP address setting. 710-711 troubleshooting CHAP authentication failures. 477-479 ACL interactions with routergenerated packets. See TCP transparent mode (VTP). 563 version mismatches. 561 routers configuring different VIPs. 572 DHCP issues. 286 verification checks. 492-493 video. 481 inbound ACL filters routing protocol packets. 406 tunnel destination. 286-288 incorrect ASNs. 409 source/destination addresses. 494 voice. 408 HSRP. 275 configuration problems. 510 traffic rate versus configured policing rate. 563 configuration. 106 channel-group command incorrect options. 483-485 common syntax mistakes. 750-751 shaping. 660 EIGRP interfaces. 106-108 configuration checks before adding interfaces.922 traffic features. 560 ACL blocks HSRP packets. 493-494 Traffic Class field (IPv6). 378.

troubleshooting 923

DNS problems, 571-572
incorrect addressing plans,
IP forwarding issues, 577-580
LAN issues, 575-576
mismatched IPv4 settings,
mismatched masks, 569-571
packet filtering with access lists,
router WAN interface status, 585
IPv6 routing, 604
ACLs, 612
filtering issues, 604
host issues, 604
host pings fail from default
router, 606-607
host pings only working in some
cases, 605-606
missing IPv6 settings in host,
name resolution problems,
router issues, 604
routes, 640-641
routing, 611-612
Layer 3 EtherChannels, 541
leased-line WANs, 353-354
Layer 1 problems, 354
Layer 2 problems, 354-356
Layer 3 problems, 357-358
mismatched subnets, 358
neighbors, 285
MTU mismatched settings, 296
processes, shutting down,

9781587205798_BOOK.indb 923

OSPF interfaces, 281-283
area design, 281
configuration errors, 282-283
details, checking, 283
unsolicited log messages, 283
OSPF neighbors, 288-294
area mismatches, finding,
duplicate RIDs, 291-293
Hello timer/dead timer
mismatches, 293-294
LAN problems, 289
neighbor states, 288
interfaces, 631-632
neighbors, 633-635
PAP authentication failures, 356
PPPoE, 425-426
customer router configuration,
dialer 2 status, 427
Layer 1, 427-428
Layer 2, 428-429
Layer 3, 429
summary, 430
ROAS, 528-529
routing protocols
configuration errors, 274
internetwork, analyzing, 273
neighbor relationships, 274
routing tables, 273
routing with SVIs, 532-534
RP problems, 103
SPAN sessions, 725
standard numbered ACLs, 452-453

6/1/16 12:04 PM



convergence, 105-106
DPs on LAN segments, 104-105
root switch election, 99-101
RPs on nonroot switches,
switch data plane forwarding
EtherChannel impact on MAC
tables, 111-112
STP impact on MAC tables, 110
VLAN of incoming frames,
access interfaces, 113-114
frame switching problems, 113
undefined/disabled VLANs,
VLAN trunking
frame switching problems, 113
mismatched native VLANs, 118
mismatched operational states,
mismatched supported VLAN
lists, 117-118
VTP, 135
adding switches, 137-139
common configuration rejections,
synchronization, 136-137
trunking (VLANs)
802.1Q, 20-21
configuration, 30-34
disabling, 139
ISL (Inter-Switch Link), 20-21
overview, 18
protocol. See VTP
troubleshooting, 113-118
VLAN tagging, 18-20

9781587205798_BOOK.indb 924

trust boundaries (QoS marking),
trusted ports, 151
configuring, 153
DHCP snooping, 154
tunnel destination command, 406-408,
tunnel mode gre ip command, 404,
tunnel mode gre multipoint command,
tunnel source command, 406-407, 432
destinations, 408
GRE, 398
between routers, 399
configuring, 402-404
details, displaying, 404
functionality, testing, 406
large scale environments, 411
multipoint with DMVPN, 411
point-to-point, 399
routes, 405
troubleshooting, 406-410
tunnel interfaces, 398
unsecured networks, 400-401
verifying, 404-406
ACLs, 409-410
creating, 400
destinations, 408
Layer 3 issues, 409
replacing serial links, 398
state, 407
VPN, 394-395
tutorial (exam), 784-785

6/1/16 12:04 PM

verifying 925

Twitter (Wendell Odom), 799
Type of Service (ToS) field (IPv4), 499

UCS (Unified Computing System), 733
UDP (User Datagram Protocol)
Jitter probes, 713
packets, IPv6 ACL matching, 675
port numbers, matching, 464-467
undebug all command, 298
undefined VLANs, troubleshooting,
unequal-cost load balancing, 263
UNI (user network interface), 365
unicast IPv6 addresses, 593-595
Unified Computing System (UCS), 733
unique local unicast addresses, 593
unsecured networks (GRE tunnels),
unsolicited log messages, 283
untrusted ports, 151-154
upd keyword, 464
BGP, 303, 310
DV protocols, 229-230
EIGRP, 235-236
full, 229
partial, 232
periodic, 229
User Datagram Protocol. See UDP
user network interface (UNI), 365
username command, 345, 359
U.S. National Institute of Standards
and Technology (NIST), 739

9781587205798_BOOK.indb 925

v1default MIB view, 706
variable length subnet masking. See
variables (MIB)
monitoring, 696
numbering/names, 697
variance (EIGRP), 263-264
variance command, 270
EIGRP for IPv4, 247, 263, 647
EIGRP for IPv6, 651, 662
vCPU (virtual CPU), 734
vector (DV protocols), 228
verification command, 75
BPDU Guard, 82-83
data and voice VLANs, 36-38
eBGP neighbors, 312-313
EIGRP configuration, 249
EIGRP enabled interfaces,
finding, 250-252
IPv4 routing table, displaying,
neighbor status, displaying, 253
EIGRP for IPv6
interfaces, 654
routes, 659-660
EIGRP neighbors, 235, 285-286
EtherChannel configuration before
adding interfaces, 108-109
GRE tunnels, 404-406
HDLC, 339
HSRP, 555-556
interarea OSPF routes, 212

6/1/16 12:04 PM

See VMs network functions virtualization (NFV). 131-133 username/passwords on AAA servers. See VLANs virtual machines. See VMs virtual network functions (VNFs). 734 multithreading. 630-631. 531 SNMPv2 configuration. 734 networking. 420-421 dialers. 735 routers (public cloud networks). 424 virtual-access interfaces. 737-738 firewalls. 423 virtual LANs. 702-704 SNMPv3 configuration. 219-221 multiarea. 754 CPU (vCPU).926 verifying IPv6 connectivity. 494 shaping time intervals. 421-422 Layer 3 status. 734 data centers networking. 754 machines. 734-735 hosts. 423 ROAS. 210-212 single-area. 526-527 routing protocol-enabled interfaces. 735-736. 632-633 PortFast. 705 virtual-access interfaces. 600 hosts. 754 servers. 75-77 switches synchronization to VLAN database. 600-601 routers. 619 VTP. 736 6/1/16 12:04 PM . 367 Virtual Router Redundancy Protocol (VRRP). 708-709 standard numbered ACLs. 274 routing with SVIs. See VPNs Virtual Private Wire Service (VPWS). 425 session status. 638-640 neighbors. 754 NICs (vNICS). 127 9781587205798_BOOK. 351-353 OSPFv2 configurations interfaces. 735 workflow. 345-346 PAP. 544 virtualization ASA firewall (ASAv). 347 PPPoE. 735 physical networks. 754 networks. 539-540 MLPPP. 752-754 Virtual Private LAN Service (VPLS). 601-603 Layer 3 EtherChannels. 367 Virtual Private Networks. 82-83 PPP CHAP. 452-453 STP.indb 926 video traffic QoS requirements. 200-202 OSPFv3 interfaces. 734 hypervisors. 736 vendors. 512 views (MIB). 145 versions HSRP. 559-560 OSPF.

21-23 VLAN Trunking Protocol. 25-28 overview. 125-126 full VLAN configuration example. 21 Layer 3 EtherChannels configuring. choosing. 18-20 troubleshooting access interfaces. switches synchronization. 123 9781587205798_BOOK. 30-34 disabling. 25. 526-527 routers. 524 configuration. See SVIs IP telephony. 525-526 overview. See VLAN routing SPAN monitoring. 137 vlan command. 23-24. 34-36 data and voice VLAN configuration and verification. 112-113 interfaces. 114-115 trunking 802. 24-25 shorter VLAN configuration example. 18 protocol. VTP synchronization. 721 standard range. 534-537 Layer 3 switching with SVIs configuring. 537-539 troubleshooting. 113-118 VLAN tagging. 18-20 vlan 10 command. 735 VMs. adding. 735 VLANs (virtual LANs) configuration data and voice VLANs. 40. 115 IDs. 122 mismatched native on trunks. 139 ISL (Inter-Switch Link). 131-133 default. 20-21 configuration. 20. 532-534 verifying. 34 data and voice VLAN concepts. 118 mismatched supported trunk lists. 734 switches (vSwitches). 20-21 overview. 529-531 troubleshooting.indb 927 tagging. 36-38 summary. 38-39 LAN support. 113-114 frame switching process problems. 16-18 routing. 36-38 database. See VTP 6/1/16 12:04 PM . 135 VLAN routing. 117-118 native. 539-540 Layer 3 switch routed ports. 113 undefined/disabled VLANs. 18 incoming frames. 30-34 database. 524-526 troubleshooting. 541 verifying. 531 ROAS. 28-29 trunking. 25 enabling/disabling. 122 vlan 200 command.1Q. 528-529 verifying. See VTP troubleshooting.VLAN Trunking Protocol 927 virtual data center vendors. 37.

379-382 OSPF area design. 137 synchronization. 129 steps. troubleshooting. 393 MPLS VPNs. 129 example. 131-133 synchronization. 134 6/1/16 12:04 PM . 735 VTP (VLAN Trunking Protocol). 394-396 tunnels. 127-128 requirements. 123 vtp commands. 120 configuration common rejections. 389 benefits. 752-754 vNICs (virtual NICs). 367 VRRP (Virtual Router Redundancy Protocol). 742 virtual NICs (vNICs). 120 automated update powers. 734 ACI. 493 QoS requirements. 135 troubleshooting. 493-494 VPLS (Virtual Private LAN Service). 125 transparent mode. 137-139 common configuration rejections. 411 NHRP (Next Hop Resolution Protocol). 381-382 public cloud. 125-127 features. 129 storing. 412-413 Internet. 735 voice switches. 378. 134-135 domains. 743 spinning up. 123 switches synchronization to VLAN database. 742 networking. 494 shaping time intervals. 382 Layer 3. adding. 378 VoIP (Voice over IP). 130-131 new VTP configuration settings. 735 VNFs (virtual network functions). 773 IaaS. 394-395 VPWS (Virtual Private Wire Service). 367 VPNs (Virtual Private Networks) client. 394 security. 29. 512 VoIP. 743-744 SaaS.indb 928 site-to-site. 544 vSwitches (virtual switches). 126-127 servers. 124 standard range VLANs. accessing. 747 9781587205798_BOOK. 736 PaaS. 130 planning. verifying.928 VLSM (variable length subnet masking) VLSM (variable length subnet masking) overlapping subnets. 581 VMs (virtual machines). 136-137 versions. 135 adding switches. 411 multipoint GRE tunnels. 137 default VTP settings. 396-397 dynamic multipoint (DMVPN). 34 voice traffic. 127 VLAN support. 376 EIGRP challenges. 128 pruning. 583-585 recognizing when VLSM is used.

336 leased-line with PPP authentication. See MLPPP PPP functions. 333-334 troubleshooting. 377 MPLS VPNs. 389 Internet as WAN service. 747 Frame Relay. 335-336 CSU/DSUs. 746-749 service providers (SPs). 367-371 E-Tree service. 29. 140 W–Z WANs Ethernet. See wildcard masks 6/1/16 12:04 PM . 332 WC masks. 365-366 Point-to-Point topology. 140 vtp mode command. 362 public cloud connections Internet as. 332-333 speeds. 392-393 WAN interface cards (WICs). 40. 337-340 de-encapsulating/ re-encapsulating IP packets. 370-372 MEF. 368 hub and spoke topology. 134. 342-343 configuring PPP. 334 mismatched subnets. 369-372 full mesh topology. 389 leased-line. 362 wireless. 490 Internet access. 135 vtp password command. 378-379 VPNs. 751 types. 366 Layer 3 design.indb 929 929 multilink. 140 vtp version command. 140 vtp mode off command. 135 vtp mode transparent command.WC masks vtp domain command. 346-347 control protocols. 365 data usage. 366 MPLS. 134. 376 private public cloud access. 362 interface speeds. 366 partial mesh topology. 745-746 private WANs. 358 physical components. 353-358 leased-line with HDLC. 341 framing. 369 IEEE Ethernet standards. 343-344 configuring PPP CHAP. 134. 378 Layer 3 design. 336 configuring HDLC. 375-377 access links. 746-749 public cloud branch office connections. 368-372 E-Line service. 340 MetroE. 140 vtp pruning command. 134. 341 9781587205798_BOOK. 367-368 services. 344-346 configuring PPP PAP. 29. 373-375 E-LAN service. 336 framing. 330-331 building. 369 physical design. 364 access links. 379-382 QoS.

198 wildcard masks binary. 744 IANA. 695 Eclipse IDE. 771 OpenFlow. 505 Wendell Odom’s SDN Skills blog. 706 6/1/16 12:04 PM . 777 APIC-EM labs. 248-249 finding. 754 Google App Engine PaaS. 174 BGP routing table analysis reports. 768 Pearson Network Simulator (the Sim). 682 ICMPv6 packets. 777 DevNet. 737-738 working interfaces. 446-447 EIGRP configuration. 744 ETSI. 447 decimal. 199 wireless Internet. 669 IPv6 multicast address space registry. 744 9781587205798_BOOK. 448 OSPF single-area configuration. 174 ICMPv6 parameters. 777 WICs (WAN interface cards). 774 APIC-EM pages. 718 workflow (virtualized data center). 777 Wireshark network analyzer.indb 930 MEF. 332 wildcard_mask parameter (network command). 796 CCNA Routing and Switching ICND2 Official Cert Guide. 366 OpenDaylight SDN controller. 777 Cisco ACI.930 websites websites APIC-EM Analysis tool released code. 777 ARIN. 669 Jenkins continuous integration and automation tool. 392-393 Wireshark network analyzer. 796 Wendell Odom’s SDN Skills. 303 CCNA (ICND2) Config Labs. 777 Feature Navigator. 49 write views (SNMPv3 groups). 531 Prime management products. 718 weighting. 393 wireless WANs.

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