fm.fm Page i Monday, March 20, 2000 4:55 PM Cisco CCNA Exam #640-507 Certification Guide Wendell Odom, CCIE #1624 Cisco Press 201 W 103rd Street Indianapolis, IN 46290 fm.fm Page ii Monday, March 20, 2000 4:55 PM ii Cisco CCNA Exam #640-507 Certification Guide Wendell Odom Copyright© 2000 Lacidar Unlimited, Inc Cisco Press logo is a trademark of Cisco Systems, Inc Published by: Cisco Press 201 West 103rd Street Indianapolis, IN 46290 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 review Printed in the United States of America Library of Congress Cataloging-in-Publication Number: 99-67898 ISBN: 0-7357-0971-8 Warning and Disclaimer This book is designed to provide information about the Cisco CCNA #640-507 exam 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 author, 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 mark Feedback Information At Cisco Press, our goal is to create in-depth technical books of the highest quality and value Each book is crafted with care and precision, undergoing rigorous development that involves the unique expertise of members from the professional technical community Readers’ feedback is a natural continuation of this process If you have any comments regarding how we could improve the quality of this book, or otherwise alter it to better suit your needs, you can contact us through e-mail at ciscopress@mcp.com Please make sure to include the book title and ISBN in your message We greatly appreciate your assistance fm.fm Page iii Monday, March 20, 2000 4:55 PM iii Publisher Executive Editor Cisco Systems Program Manager Managing Editor Development Editor Senior Editor Copy Editor Technical Editors Team Coordinator Book Designer Cover Designer Production Team Indexer Corporate Headquarters Cisco Systems, Inc 170 West Tasman Drive San Jose, CA 95134-1706 USA http://www.cisco.com Tel: 408 526-4000 800 553-NETS (6387) Fax: 408 526-4100 John Wait John Kane Jim LeValley Patrick Kanouse Christopher Cleveland Jennifer Chisholm Krista Hansing David Barnes Tinjin Chang Steve Kalman Frank Knox Barbara Nolley Amy Lewis Gina Rexrode Louisa Klucznik Argosy Christopher Cleveland European Headquarters Cisco Systems Europe s.a.r.l Parc Evolic, Batiment L1/L2 16 Avenue du Quebec Villebon, BP 706 91961 Courtaboeuf Cedex France http://www-europe.cisco.com Tel: 33 69 18 61 00 Fax: 33 69 28 83 26 American Headquarters Cisco Systems, Inc 170 West Tasman Drive San Jose, CA 95134-1706 USA http://www.cisco.com Tel: 408 526-7660 Fax: 408 527-0883 Asia Headquarters Nihon Cisco Systems K.K Fuji Building, 9th Floor 3-2-3 Marunouchi Chiyoda-ku, Tokyo 100 Japan http://www.cisco.com Tel: 81 5219 6250 Fax: 81 5219 6001 Cisco Systems has more than 200 offices in the following countries Addresses, phone numbers, and fax numbers are listed on the Cisco Connection Online Web site at http://www.cisco.com/offices Argentina • Australia • Austria • Belgium • Brazil • Canada • Chile • China • Colombia • Costa Rica • Croatia • Czech Republic • Denmark • Dubai, UAE Finland • France • Germany • Greece • Hong Kong • Hungary • India • Indonesia • Ireland • Israel • Italy • Japan • Korea • Luxembourg • Malaysia • Mexico • The Netherlands • New Zealand • Norway • Peru • Philippines • Poland • Portugal • Puerto Rico • Romania • Russia • Saudi Arabia • Singapore • Slovakia • Slovenia • South Africa • Spain • Sweden • Switzerland • Taiwan • Thailand • Turkey • Ukraine • United Kingdom • United States ã Venezuela Copyright â 2000 Cisco Systems, Inc All rights reserved Printed in the USA Access Registrar, AccessPath, Any to Any, AtmDirector, CCDA, CCDE, CCDP, CCIE, CCNA, CCNP, CCSI, CD-PAC, the Cisco logo, Cisco Certified Internetwork Expert logo, CiscoLink, the Cisco Management Connection logo, the Cisco NetWorks logo, the Cisco Powered Network logo, Cisco Systems Capital, the Cisco Systems Capital logo, Cisco Systems Networking Academy, the Cisco Systems Networking Academy logo, the Cisco Technologies logo, ConnectWay, ControlStream, Fast Step, FireRunner, GigaStack, IGX, Internet Quotient, Kernel Proxy, MGX, Natural Network Viewer, NetSonar, Network Registrar, Packet, PIX, Point and Click Internetworking, Policy Builder, Precept, RouteStream, Secure Script, ServiceWay, SlideCast, SMARTnet, StreamView, The Cell, TrafficDirector, TransPath, ViewRunner, VirtualStream, VisionWay, VlanDirector, Workgroup Director, and Workgroup Stack are trademarks; Changing the Way We Work, Live, Play, and Learn, Empowering the Internet Generation, The Internet Economy, and The New Internet Economy are service marks; and ASIST, BPX, Catalyst, Cisco, Cisco IOS, the Cisco IOS logo, Cisco Systems, the Cisco Systems logo, the Cisco Systems Cisco Press logo, Enterprise/Solver, EtherChannel, EtherSwitch, FastHub, FastLink, FastPAD, FastSwitch, GeoTel, IOS, IP/TV, IPX, LightStream, LightSwitch, MICA, NetRanger, Registrar, StrataView Plus, Stratm, TeleRouter, and VCO are registered trademarks of Cisco Systems, Inc and/or its affiliates in the U.S and certain other countries All other trademarks mentioned in this document are the property of their respective owners The use of the word partner does not imply a partnership relationship between Cisco and any of its resellers (9908R) fm.fm Page iv Monday, March 20, 2000 4:55 PM iv About the Author Wendell Odom has worked with networking technology for 15 years He is currently a Cisco Systems Senior Systems Engineer in the Atlanta, Georgia office, assigned to several large Cisco customers Prior to joining Cisco in 1999, Wendell provided consulting services on large networks as well as training services He spent his first eight years in networking working for IBM, helping customers evolve their SNA networks into multiprotocol networks Wendell is CCIE #1624, is a Certified Cisco Systems Instructor, is Cisco CIPcertified, and is a CCNA-WAN He has taught various Cisco-certified courses, including Introduction to Cisco Router Configuration (ICRC), Advanced Cisco Router Configuration (ACRC), Cisco SNA for Multiprotocol Administrators (SNAM), Cisco Channel Interface Processor (CIP), MPLS over Cisco WAN Switches, and Cisco ATM (CATM) Wendell is one of the first Cisco instructors certified without a probationary testing period and is the first non-Cisco instructor in the United States to teach Cisco’s SNAM, CIP, and DLSw courses About the Technical Reviewers David Barnes is a Network Consulting Engineer for Cisco Systems in Dallas, Texas He is a Cisco Certified Design Professional, MCSE+Internet, and Master CNE David specializes in large-scale network design and optimization He has designed, implemented, and managed networks for numerous Fortune 500 companies over the past 10 years Tinjin Chang, CCIE #5137 and CCSI, is an instructor and consultant for Chesapeake Network Solutions, Inc Tinjin has more than seven years of experience in planning, deploying, and troubleshooting complex and large-scale IP and multiprotocol networks Prior to joining Chesapeake, he was the lead network engineer at Discover Brokerage, where his design and troubleshooting skills minimized downtime and guaranteed network availability Discover Brokerage was named the Best Online Broker by Barron’s magazine for the two years that he worked there Steve Kalman is a data communications trainer He is the author or tech editor of 12 CBT titles and has been the author, tech editor, or trainer for eight instructor-led courses Steve also is beginning a new distance-learning project as both author and presenter In addition to those responsibilities, he runs a consulting company, Esquire Micro Consultants, that specializes in data network design Frank Knox, CCIE #3698, is a consultant and instructor currently involved in design, implementation, and customer training for mixed SNA-IP networks He is considered to be an expert in the area of mainframe attached routers Frank has more than 33 years of networking experience with IBM, GTE, and Skyline Computer Corp.; during that time, he has worked in field service and support, product planning, education, and management In addition, he has developed and taught several courses for the University of Dallas (Telecommunications MBA program) Frank has a master’s degree in telecommunications from Pace University Barb Nolley is the president and principal consultant for BJ Consulting, Inc., a small consulting firm that specializes in networking education Since starting BJ Consulting, Barb has developed and taught training courses for Novell’s Master CNE certification, as well as several courses for Cisco System’s Engineering Education group Barb stays current on networking technologies by constantly reading published books and perusing more than 50 industry publications each month Prior to starting her own company in 1993, Barb worked for Apple Computer, Tandem Computer, and Tymnet (now part of MCI), where she held positions in everything from technical support to project management fm.fm Page v Monday, March 20, 2000 4:55 PM v Dedication My wife, Kris, was a great help to me during this latest writing project While she took no direct role in the book, everything I in life is a lot better because the love of my life is with me! Thanks to my parents, Raymond and Fay, who took care of many things during some health problems I had while writing the book And finally, but most importantly, thanks to Jesus Christ, especially for your joy, peace, and protection in the midst of a tough year fm.fm Page vi Monday, March 20, 2000 4:55 PM vi Acknowledgments Chris Cleveland, development editor for Cisco Press, is the best in the business! Chris made my job much easier so that I could concentrate totally on the content I’d probably refuse to write another book if Chris wouldn’t be the development editor! John Kane, executive editor for Cisco Press, provided a great deal of assistance, as usual John’s frequent e-mails and conference calls with Cisco’s Worldwide Training organization allowed him to gather the information needed to guide Cisco Press’s Cisco certification books, and it also allowed me to focus on writing, instead of sending e-mails and participating in conference calls! Thanks for everything, John Many people at Cisco Press have helped make this book a success Amy Lewis helped greatly by taking care of many details Many others worked behind the scenes, and although I never met them, they are appreciated! Cisco Press spends much more time producing the book than I to simply write it—they have the laborious tasks! Thanks to all on the team! The technical editors deserve most, if not all, of the credit for making the content robust and complete There is no question that the book is immensely better after the edit process! While all the editors gave a great deal of help, each brought some particular strengths to the task Tinjin, thanks for pointing out topics for which just a little deeper technical coverage would help to clear up a topic Steve, thanks for the input relating to points that come up in the many classes you teach David, thanks for jumping into the fray in the middle of the process and adding some great help Barb, you get the most credit for removing errors from the book! (Of course, I take full responsibility for any remaining errors.) And, to my old friend Frank, thanks for all the help and the occasional good-bad joke in your editing comments! (An example: “What’s a gateway? About 50 pounds!” If you didn’t get it, “gateway” sounds like “gate weigh.”) All the technical editors were an immense help fm.fm Page vii Monday, March 20, 2000 4:55 PM vii Contents at a Glance Introduction xx Chapter All About the Cisco Certified Network Associate Certification Chapter Cisco Internetwork Operating System (IOS) Fundamentals Chapter OSI Reference Model & Layered Communication Chapter Bridges/Switches and LAN Design Chapter Network Protocols Chapter Routing Chapter Understanding Access List Security Chapter WAN Protocols and Design Chapter Scenarios for Final Preparation Appendix A Answers to the “Do I Know This Already?” Quizzes and Q&A Sections Appendix B Decimal to Hexadecimal and Binary Conversion Table Index 786 20 68 128 210 352 454 514 638 776 700 fm.fm Page viii Monday, March 20, 2000 4:55 PM viii Table of Contents Introduction xx Chapter All About the Cisco Certified Network Associate Certification How This Book Can Help You Prepare and Pass the CCNA Exam Overview of Cisco Certifications Exams Required for Certification Other Cisco Certifications What’s on the CCNA Exam Topics on the Exam Recommended Training Path for CCNA 11 How to Use This Book to Pass the Exam 12 I’ve Taken ICND—Now What? 14 I’ve Taken ICRC—Now What? 15 I’ve Taken the Cisco Networking Academy Courses—Now What? 16 I’m New to Internetworking with Cisco, and I Will Not Be Taking the ICND Course— Now What? 17 I’ve Learned a Lot About CCNA Topics Through Experience, But I Will Not Be Taking the ICND Course—Now What? 18 Conclusion 18 Chapter Cisco Internetwork Operating System (IOS) Fundamentals How to Best Use This Chapter 21 “Do I Know This Already?” Quiz 22 The IOS and Its User Interface 26 Router Components 26 Command-Line Interface 28 Navigating the IOS CLI 30 Configuration Processes and the Configuration File Example Configuration Process 37 Managing Configuration Files 39 Cisco Discovery Protocol (CDP) 45 Managing IOS Images 48 34 20 fm.fm Page ix Monday, March 20, 2000 4:55 PM ix Upgrading an IOS Image into Flash Memory Choosing Which IOS Image to Load 50 Scenario 2-1 61 Questions on Scenario 2-1 62 Scenario 2-2 63 Questions on Scenario 2-2 63 Scenario 2-1 Answers 66 Scenario 2-2 Answers 66 Chapter OSI Reference Model & Layered Communication How to Best Use This Chapter 48 68 69 “Do I Know This Already?” Quiz 70 The OSI, TCP/IP, and NetWare Protocol Architectures OSI: Origin and Evolution 74 OSI Layers 75 Layering Benefits and Concepts 78 Interaction Between OSI Layers 79 The TCP/IP and NetWare Protocols 86 74 OSI Transport Layer Functions 87 Connection-Oriented Versus Connectionless Protocols How Error Recovery Is Accomplished 89 Flow Control 91 OSI Data Link Layer Functions 94 Data Link Function 1: Arbitration 95 Data Link Function 2: Addressing 96 Data Link Function 3: Error Detection 98 Data Link Function 4: Identifying the Encapsulated Data Summary: Data Link Functions 102 OSI Network Layer Functions 103 Routing 103 Network Layer (Layer 3) Addressing Scenario 3-1 121 Task for Scenario 3-1 Task for Scenario 3-1 Task for Scenario 3-1 122 123 123 Answers to Task for Scenario 3-1 124 107 87 98 fm.fm Page x Monday, March 20, 2000 4:55 PM x Answers to Task for Scenario 3-1 124 Answers to Task for Scenario 3-1 126 Chapter Bridges/Switches and LAN Design 128 How to Best Use This Chapter 129 “Do I Know This Already?” Quiz 130 LAN Overview 135 LAN Addressing 138 LAN Framing 140 Fast Ethernet and Gigabit Ethernet LAN Standards 143 142 Bridging, Switching, and Spanning Tree 145 Transparent Bridging 145 LAN Switching 148 Comparison of LAN Segmentation Using Bridges, Switches, and Routers Spanning Tree 158 Virtual LANs 171 VLAN Summary 177 LAN Switch Configuration 177 Basic 1900 Switch Configuration 178 Basic VLAN Configuration 187 VLAN Trunking Protocol (VTP) 194 Chapter Network Protocols 210 How to Best Use This Chapter 211 “Do I Know This Already?” Quiz 212 TCP/IP Protocols 217 Transmission Control Protocol 217 User Datagram Protocol 224 Address Resolution Protocol 226 Internet Control Message Protocol 227 FTP and TFTP 232 IP Addressing and Subnetting 235 IP Addressing Review 235 Five Ways the Exam Will Test Your IP Addressing Knowledge CIDR, Private Addressing, and NAT 267 244 155 ... the Cisco Certified Network Associate Certification How This Book Can Help You Prepare and Pass the CCNA Exam Overview of Cisco Certifications Exams Required for Certification Other Cisco Certifications... 2000 4:55 PM ii Cisco CCNA Exam #640-507 Certification Guide Wendell Odom Copyright© 2000 Lacidar Unlimited, Inc Cisco Press logo is a trademark of Cisco Systems, Inc Published by: Cisco Press 201... Economy are service marks; and ASIST, BPX, Catalyst, Cisco, Cisco IOS, the Cisco IOS logo, Cisco Systems, the Cisco Systems logo, the Cisco Systems Cisco Press logo, Enterprise/Solver, EtherChannel,