CCNA Self-Study CCNA INTRO Exam Certification Guide

Cisco Press
201 West 103rd Street
Indianapolis, IN 46290 USA

Cisco Press
CCNA Self-Study

CCNA INTRO
Exam Certification Guide

Wendell Odom, CCIE No. 1624

0945_01f.book Page i Wednesday, July 2, 2003 3:53 PM

ii

CCNA INTRO Exam Certification Guide

Wendell Odom
Copyright© 2004 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 permis-
sion from the publisher, except for the inclusion of brief quotations in a review.
Printed in the United States of America 1 2 3 4 5 6 7 8 9 0
First Printing August 2003

Library of Congress Cataloging-in-Publication Number:

2003104998
ISBN: 1-58720-094-5

Warning and Disclaimer

This book is designed to provide information about selected topics for the Introduction to Cisco Networking Technologies
(INTRO) exam for the CCNA 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.

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All terms mentioned in this book that are known to be trademarks or service marks have been appropriately capitalized.
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iii

Publisher:

John Wait

Cisco Representative:

Anthony Wolfenden

Editor-In-Chief:

John Kane

Cisco Press Program Manager:

Sonia Torres Chavez

Executive Editor:

Brett Bartow

Cisco Marketing Communications Manager:

Scott Miller

Managing Editor:

Patrick Kanouse

Cisco Marketing Program Manager:

Edie Quiroz

Development Editor:

Christopher Cleveland

Technical Editors:

Elan Beer, Lynn Maynes, Martin Walshaw

Project Editor:

Marc Fowler

Copy Editor:

Krista Hansing

Team Coordinator:

Tammi Barnett

Book Designer:

Louisa Adair

Cover Designer:

Louisa Adair

Compositor:

Mark Shirar

Indexer:

Tim Wright

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iv

About the Author

Wendell Odom, CCIE No. 1624,

is a senior instructor with Skyline Computer
(www.skylinecomputer.com), where he currently teaches courses on QoS, CCNA, and CCIE
lab preparation. Wendell has worked in the networking arena for 20 years, with jobs in pre-
and post-sales technical consulting, teaching, and course development. He has authored
portions of more than 12 courses, including topics such as IP routing, MPLS, Cisco WAN
switches, SNA protocols, and LAN troubleshooting. He is author of three previous editions
of the

CCNA Exam Certification Guide

as well as the

Cisco Press DQOS Exam Certification
Guide

.

About the Technical Reviewers

Elan Beer

, CCIE No. 1837, CCSI No. 94008, is a Senior Consultant and Certified Cisco
Instructor. Elan’s internetworking expertise is recognized internationally through his global
consulting and training engagements. As one of the industry’s top internetworking
consultants and Cisco instructors, Elan has utilized his expertise to design, implement, and
deploy multiprotocol networks for a wide range of international clientele. As a senior
instructor and course developer, Elan has designed and presented public and
implementation-specific technical courses spanning many of today’s top technologies. Elan
can be reached via e-mail at

Lynn Maynes,

CCIE No. 6569, is a senior network engineer with Sprint Managed Network
Services specializing in network design, architecture and security for large-scale networks
worldwide. He has more than 9 years of experience in computer networking and is a co-
author of the Cisco Press book

CCNA Practical Studies

. He holds a bachelor’s degree in
international business from Westminster College.


Martin Walshaw

, CCIE No. 5629, CISSP, CCNP, CCDP, is a systems engineer working for
Cisco Systems in the Enterprise Line of Business in South Africa. His areas of specialty
include convergence, security, and content delivery networking, which keeps him busy both
night and day. During the last 15 years or so, Martin has dabbled in many aspects of the IT
industry, ranging from programming in RPG III and COBOL to PC sales. When Martin is
not working, he likes to spend all of his available time with his patient wife, Val, and his sons,
Joshua and Callum. Without their patience, understanding, and support, projects such as this
would not be possible.

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v

Dedications

Chris Cleveland is the best Development Editor I could imagine working with. So, instead of
just the usual “Thanks Chris for doing an excellent job,” I’d like to dedicate this book to
Chris. Chris, it’s an absolute pleasure to work with the best in the business —thanks for your
fantastic help and support!

Acknowledgments

The technical editing team for this book and its companion volume was fantastic! Not only did they
find where I had simply written the wrong technical facts, but they also helped me find new, more

interesting, and clearer ways to convey certain facts about networking. Lynn was particular helpful
with comments that helped keep small sections in line with the overall theme of the chapter—a skill
I’m sure he developed as a result of having written books himself. Martin helped a lot with technical
detail and perspectives from what customers see every day today. And Elan excelled in noticing both
the small nit-picky errors and the significant technical problems. (And that’s not an insult—every
technical author loves help in finding the small problems!) Together, these three gentlemen formed
a great team, with complementary skills. Thanks so much, guys!
The production team, headed by Patrick Kanouse, did its usual excellent job. Like the
behind-the-scenes people in many businesses, their specific efforts may not be obvious to the
public, but it’s no less appreciated by me. In particular, Marc Fowler, the project editor, did
an incredible job working through these two books on a very tight schedule, with his usual
excellent work. You folks make me look good on paper all the time—if only you could be in
charge of my wardrobe, too—I’d look good all the time!
Brett Bartow, executive editor, did his usual New-York-Yankees-like job in helping steer these
two projects to completion. In between talking about sports, Brett worked through the many
changes in direction with this book and helped guide us to the right product. And, yes, so the
whole world knows, he did pick an Atlanta Braves player, John Smoltz, for his fantasy league
baseball team—again proving he’s a really smart guy.
Chris “develops” books for Cisco Press. What does that mean? Well, it means that he takes
the Word documents and figures from geeky authors, and makes their writing become
understandable. He takes the input from technical editors, and combines all the comments
into a single word document, making the author’s life easier. He constantly finds ways to
rephrase, reword, and improve the manuscript. He manages all the work with the authors.
And he always works to optimize the author’s time, taking away some of the unpleasant part
of the work, so that the author can worry about the technical details. Chris has worked with
me on 6 projects now, and every time, he has done an excellent job. His work ethic goes far
beyond the call of duty, and his performance is consistently excellent. To quote a few other
authors as well: “Chris has taken all of the difficulty (of writing) out of the picture”, “Chris
has absolutely spoiled me and completely amazes me”, and “He even helped me with my
daughter’s homework”. Whatever, however, to make the book better, with an eye towards

the least pain for the author, Chris is on top of it. Thanks, Chris, for all you do!

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vi

Contents at a Glance

Introduction xvii

PART I: Networking Fundamentals 3

Chapter 1 Introduction to Computer Networking Concepts 5
Chapter 2 The TCP/IP and OSI Networking Models 15
Chapter 3 Data Link Layer Fundamentals: Ethernet LANs 43
Chapter 4 Fundamentals of WANs 77
Chapter 5 Fundamentals of IP 109
Chapter 6 Fundamentals of TCP and UDP 145

PART II: Operating Cisco Devices 169

Chapter 7 Operating Cisco Routers 171
Chapter 8 Operating Cisco LAN Switches 209

PART III: LAN Switching 227

Chapter 9 Cisco LAN Switching Basics 229
Chapter 10 Virtual LANs and Trunking 259
Chapter 11 LAN Cabling, Standards, and Topologies 279

PART IV: TCP/IP 311

Chapter 12 IP Addressing and Subnetting 313
Chapter 13 Basic Router Configuration and Operation 363
Chapter 14 Introduction to Dynamic Routing Protocols 403

PART V: Wide-Area Networking 427

Chapter 15 Remote Access Technologies 429

PART VI: Final Preparation 477

Chapter 16 Final Preparation 479

PART VII: Appendixes 497

Appendix A Answers to the “Do I Know This Already?” Quizzes and Q&A Sections 499
Appendix B Binary/Decimal Conversion Chart 565
Appendix C Using the Simulation Software for Hands-on Exercises 571
Glossary 577
Index 593

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Contents

Introduction xvii

Part I Networking Fundamentals 3

Chapter 1 Introduction to Computer Networking Concepts 5

Perspectives on Networking 5

The Flintstones Network: The First Computer Network? 7

Chapter 2 The TCP/IP and OSI Networking Models 15

“Do I Know This Already?” Quiz 16
Foundation Topics 20
The TCP/IP Protocol Architecture 21

The TCP/IP Application Layer 22
The TCP/IP Transport Layer 24
The TCP/IP Internetwork Layer 26
The TCP/IP Network Interface Layer 27
Data Encapsulation 29

OSI Reference Model 31

OSI Layers 31
OSI Layering Concepts and Benefits 34
OSI Terminology 35
OSI Summary 37

Foundation Summary 38
Q&A 41

Chapter 3 Data Link Layer Fundamentals: Ethernet LANs 43

“Do I Know This Already?” Quiz 43
Foundation Topics 47
OSI Perspectives on Local-Area Networks 47

Typical LAN Features for OSI Layer 1 47
Typical LAN Features for OSI Layer 2 50

Data Link Function 1: Arbitration 50
Data Link Function 2: Addressing 51
Data Link Function 3: Error Detection 51
Data Link Function 4: Identifying the Encapsulated Data 52
Early Ethernet Standards 52

Standards Overview 53
The Original Ethernet Standards: 10BASE2 and 10BASE5 53

Repeaters 55

10BASE-T Ethernet 56

Ethernet 10BASE-T Cabling 57
10BASE-T Hubs 59

Performance Issues: Collisions and Duplex Settings 60

Reducing Collisions Through LAN Switching 60
Eliminating Collisions to Allow Full-Duplex Ethernet 62

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Ethernet Data-Link Protocols 63

Ethernet Addressing 64
Ethernet Framing 65
Identifying the Data Inside an Ethernet Frame 66
Layer 2 Ethernet Summary 68

Recent Ethernet Standards 68

Fast Ethernet 68
Gigabit Ethernet 69

Foundation Summary 70
Q&A 74

Chapter 4 Fundamentals of WANs 77

“Do I Know This Already?” Quiz 77
Foundation Topics 81
OSI Layer 1 for Point-to-Point WANs 81

WAN Connections from the Customer Viewpoint 84

WAN Cabling Standards 85
Clock Rates, DCE, and DTE 88
Link Speeds Offered by Telcos 89

OSI Layer 2 for Point-to-Point WANs 91

HDLC 91
Point-to-Point Protocol 92
Other Point-to-Point WAN Data-Link Protocols 94
Synchronization 94
Point-to-Point WAN Summary 95

Packet-Switching Services 95

Frame Relay 96

Frame Relay Basics 97

ATM and SONET 100

SONET 100
ATM 101

WAN Terminology Related to Packet Switching 102

Foundation Summary 104
Q&A 106

Chapter 5 Fundamentals of IP 109

“Do I Know This Already?” Quiz 109
Foundation Topics 114
Typical Features of OSI Layer 3 114

Routing (Path Selection) 114

PC1’s Logic: Sending Data to a Nearby Router 114
R1 and R2’s Logic: Routing Data Across the Network 115
R3’s Logic: Delivering Data to the End Destination 116

Network Layer Interaction with the Data Link Layer 116

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Network Layer (Layer 3) Addressing 118

Example Layer 3 Address Structures 119

Routing Protocols 119

IP Addressing Fundamentals 120

IP Addressing Definitions 120
How IP Addresses Are Grouped Together 121
Classes of Networks 122

The Actual Class A, B, and C Network Numbers 124
IP Subnetting 124
Network Layer Utilities 127

Address Resolution Protocol and the Domain Name System 127
ICMP Echo and the ping Command 130

RARP, BOOTP, and DHCP 130

IP Routing and Routing Protocols 133

IP Routing Protocols 135

Foundation Summary 138
Q&A 142

Chapter 6 Fundamentals of TCP and UDP 145

“Do I Know This Already?” Quiz 145
Foundation Topics 149
Typical Features of OSI Layer 4 149
The Transmission Control Protocol 150

Multiplexing Using TCP Port Numbers 151

Popular TCP/IP Applications 154

Error Recovery (Reliability) 155
Flow Control Using Windowing 156
Connection Establishment and Termination 158

Connectionless and Connection-Oriented Protocols 159

Data Segmentation and Ordered Data Transfer 160
TCP Function Summary 161

The User Datagram Protocol 161

Foundation Summary 164
Q&A 167

Part II Operating Cisco Devices 169

Chapter 7 Operating Cisco Routers 171

“Do I Know This Already?” Quiz 171
Foundation Topics 176
The Cisco IOS Software Command-Line Interface 176

Access to the CLI 176
CLI Help Features 179
The

debug

and

show

Commands 181

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Configuring Cisco IOS Software 181

Example Configuration Process 183

Router Memory, Processors, and Interfaces 187
Managing Configuration Files 188

Viewing the Configuration and Old-Style Configuration Commands 190
Initial Configuration (Setup Mode) 190
Upgrading Cisco IOS Software and the Cisco IOS Software Boot Process 194

Upgrading a Cisco IOS Software Image into Flash Memory 194
The Cisco IOS Software Boot Sequence 197

Foundation Summary 200
Q&A 204

Chapter 8 Operating Cisco LAN Switches 209

“Do I Know This Already?” Quiz 209
Foundation Topics 213
Navigating Through a Cisco 2950 Switch 213

2950 Series Features and Functions 213

2950 Switch Operating System 214

Accessing the Cisco 2950 Switch CLI 215

Switch Initialization 216

Switch LEDs During POST 216
Initial Configuration Mode 218

Configuring 2950 IOS Software 220
Foundation Summary 221
Q&A 223

Part III LAN Switching 227

Chapter 9 Cisco LAN Switching Basics 229

“Do I Know This Already?” Quiz 229
Foundation Topics 234
The Case for Bridging and Switching 234
Transparent Bridging 236

The Forward Versus Filter Decision 237
How Bridges Learn MAC Addresses 239
Forwarding Unknown Unicasts and Broadcasts 240

LAN Switching 240

Full-Duplex Ethernet 242
Internal Processing on Cisco Switches 242
Speed and Autonegotiation 244
Summary: Bridges and Switches 244

LAN Segmentation 245
The Need for Spanning Tree 248

How Spanning Tree Works 249

Foundation Summary 252

Q&A 255

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xi

Chapter 10 Virtual LANs and Trunking 259

“Do I Know This Already?” Quiz 259
Foundation Topics 263
Virtual LAN Concepts 263

VLAN Basics 263
Creating VLANs 264

Trunking with ISL and 802.1q 265

Cisco ISL 266
IEEE 802.1q 266
ISL and 802.1q Compared 267

Passing Traffic Between VLANs 268

Layer 2 Switching 268
Layer 3 Forwarding Using a Router 268
Layer 3 Forwarding Using a Layer 3 Switch 270
Layer 4 Switching 271
Layer 5–7 Switching 272
Multilayer Switching 272

Foundation Summary 274
Q&A 276

Chapter 11 LAN Cabling, Standards, and Topologies 279

“Do I Know This Already?” Quiz 279
Foundation Topics 283
Network Topologies 283
Cabling and Connectors 287

General Features of Metallic Cabling 287
Unshielded Twisted-Pair and Shielded Twisted-Pair Cabling and Connectors 289

UTP Standards 290
UTP Connectors 290

Coaxial Cabling 291
Fiber-Optic Cabling and Connectors for Ethernet 293

Optical Connectors for Ethernet 295

Summary: Ethernet Cabling 297

Ethernet Standards 297

Ethernet Framing 298
Ethernet Cabling Standards 298
10-Gigabit Ethernet 299

Wireless Communications 300

IEEE 802.11 Wireless LANs 301

Foundation Summary 303
Q&A 308

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Part IV TCP/IP 311

Chapter 12 IP Addressing and Subnetting 313

“Do I Know This Already?” Quiz 313
Foundation Topics 319
IP Addressing Review 319

IP Subnetting 321

Analyzing and Interpreting IP Addresses and Subnets 323

Math Operations Used to Answer Subnetting Questions 324

Converting IP Addresses from Decimal to Binary, and Back Again 324
The Boolean AND Operation 326
Prefix Notation 328

How Many Hosts, and How Many Subnets? 329
What Is the Subnet Number, and What Are the IP Addresses in the Subnet? 333

Finding the Subnet Number 333
Finding the Subnet Broadcast Address 335
Finding the Range of Valid IP Addresses in a Subnet 336
Finding the Answers Without Using Binary 338

What Subnet Masks Meet the Stated Design Requirements? 344
What Are the Other Subnet Numbers? 347

Scaling the IP Address Space for the Internet 351

CIDR 351
Private Addressing 353
Network Address Translation 354
IP Version 6 Addressing 355

Foundation Summary 356
Q&A 358

Chapter 13 Basic Router Configuration and Operation 363

“Do I Know This Already?” Quiz 363
Foundation Topics 368
Configuring IP Addresses 368

Basic Administrative Configuration 370
Configuring IP Addresses 372

Prefix Notation 375
Seeding the Routing Table with Connected IP Routes 375

Bandwidth, Clock Rate, and Serial Lines in the Lab 380

IP Troubleshooting Features 381

Internet Control Message Protocol 381

ICMP Echo Request and Echo Reply 382
Destination Unreachable ICMP Message 385

IP Naming Commands 387
Telnet and Suspend 389
Cisco Discovery Protocol 392
Foundation Summary 397
Q&A 400
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Chapter 14 Introduction to Dynamic Routing Protocols 403
“Do I Know This Already?“ Quiz 403
Foundation Topics 407
Routing Protocol Overview 407
Comparing and Contrasting IP Routing Protocols 408
Routing Through the Internet with the Border Gateway Protocol 410
Distance Vector Protocols: RIP and IGRP 411
Routing Information Protocol Version 1 413
RIP Version 2 414
Interior Gateway Routing Protocol 414
Link-State Protocols: OSPF and Integrated IS-IS 416
Open Shortest Path First 417
Integrated IS-IS 418

Balanced Hybrid Protocols: Enhanced IGRP 419
Summary of Interior Routing Protocols 420
Foundation Summary 422
Q&A 425
Part V Wide-Area Networking 427
Chapter 15 Remote Access Technologies 429
“Do I Know This Already?” Quiz 429
Foundation Topics 435
Perspectives on the PSTN 435
Converting Analog Voice to Digital Voice 438
Analog Modems 441
Modulation and Demodulation 442
Point-to-Point Protocol Features with Modems 444
Modem Installation and Cabling 445
Modem Standards 446
Analog Modem Summary 447
Integrated Services Digital Network 447
ISDN Channels 449
ISDN Call Setup and Data Link Protocols 449
Typical Uses of ISDN 451
ISDN Installation and Cabling 453
ISDN Summary 453
Digital Subscriber Line 454
DSL Standards 456
DSL Protocols 458
DSL Summary 459
Cable Modems 460
Layer 1 and Layer 2 between the Home and the Head End 462
Upstream Data 463
Cable Modem Summary 464

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xiv
Comparison of Remote Access Technologies 464
Foundation Summary 467
Q&A 474
Part VI Final Preparation 477
Chapter 16 Final Preparation 479
Suggestions for Final Preparation 479
Preparing for the Actual Exam Experience 480
A Final Lab Scenario 482
Scenario, Part A: Planning 482
Solutions to Part A: Planning 485
Scenario Part B: Configuration 486
Solutions to Part B: Configuration 486
Scenario Part C: Verification and Questions 488
Solutions to Part C: Verification and Questions 493
Part VII Appendixes 497
Appendix A Answers to the “Do I Know This Already?” Quizzes and Q&A Sections 499
Appendix B Decimal to Binary Conversion Table 565
Appendix C Using the Simulation Software for the Hands-on Exercises 571
Glossary 577
Index 593
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xv
Icons Used in This Book
DSU/CSU
Router Bridge Hub DSU/CSU
Catalyst
Switch
Multilayer

Switch
ATM
Switch
ISDN/Frame Relay
Switch
Communication
Server
Gateway
Access
Server
PC PC with
Software
Sun
Workstation
Macintosh
Terminal File
Server
Web
Server
Cisco Works
Workstation
Printer Laptop IBM
Mainframe
Front End
Processor
Cluster
Controller
Modem
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xvi

Command Syntax Conventions
The conventions used to present command syntax in this book are the same conventions used
in the Cisco IOS Command Reference. The Command Reference describes these conventions
as follows:
■
Vertical bars (|) separate alternative, mutually exclusive elements.
■
Square brackets [ ] indicate optional elements.
■
Braces { } indicate a required choice.
■
Braces within brackets [{ }] indicate a required choice within an optional element.
■
Boldface indicates commands and keywords that are entered literally as shown. In actual
configuration examples and output (not general command syntax), boldface indicates
commands that are manually input by the user (such as a show command).
■
Italics indicate arguments for which you supply actual values.
Network Cloud
Token
Ring
Token Ring
Line: Ethernet
FDDI
FDDI
Line: Serial
Line: Switched Serial
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xvii
Introduction: Overview of Certification and How to Succeed

Congratulations! If you’re reading far enough to look at the introduction to this book, then
you’ve probably already decided to go for your Cisco Certified Network Associate (CCNA)
certification. Cisco System’s entry-level certification, CCNA, has a reputation as one of the
most valuable entry-level certifications in the computing industry. Although getting your
CCNA does not guarantee you a first networking job or a new job, it will certainly help
convince others that you know what you are talking about.
Cisco’s CCNA certification proves that you have a firm foundation in the most important
components of the Cisco product line—namely, routers and switches. It also proves that you
have a broad knowledge of protocols and networking technologies. CCNA is not an easy
certification to get, but it is well worth the effort. In a booming economy, CCNA is the first
step toward getting a higher salary than your noncertified peers. In a difficult economy, it
could be the difference between whether a prospective employer even looks at your résumé.
Regardless of your local economy, CCNA does improve how people in the marketplace view
your skill level.
People ask me for career advice from time to time, and my answer is typically the same: If
you want to be in the networking industry at all, you need to know Cisco. Cisco has some
ridiculous market shares in the router and switch marketplace, with more than 80% market
share in some markets. In many geographies and many markets, networking equals Cisco. If
you want to be taken seriously as a network engineer, you need a CCNA certification.
Frankly, you probably also need to be working toward a more advanced Cisco certification
as well—but first things first! CCNA requires some time and effort.
Cisco’s Motivation: Certifying Partners
Cisco’s primary motivation for creating CCNA and most of the other Cisco certifications is
to help determine the skill levels of its partners. Cisco fulfills only a small portion of its orders
through direct sale from Cisco; most often, a Cisco reseller is involved. (Cisco calls resellers
channel partners.) Also, Cisco encourages partners to perform most consulting and
implementation services relating to Cisco products. While working heavily with partners,
Cisco needed to know which partners truly had the right skills. So, Cisco created many
certifications, including CCNA.
Cisco measures the technical readiness of channel partners (resellers) and professional

services partners in part by requiring specific numbers of Cisco certified employees. For
instance, Premier, Silver, and Gold Channel Partners are required to have either two or four
CCNAs on staff, along with Cisco professional- and expert-level certified individuals.
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xviii
So, what does that mean to you? Well, if you already have some Cisco certifications on your
résumé, you are more valuable to Cisco partners. In today’s competitive environment, every
edge counts—so having the right Cisco certifications can help you get that next job. In
particular, the CCNA certification is a prerequisite for almost every Cisco certification, so it
is the right place to start.
The CCNA Certification Exams: What, There’s More than One Exam?
For the first time since Cisco announced CCNA in 1998, the CCNA certification has an
option for multiple exams. Before Cisco announced these latest changes around summer of
2003, to get your CCNA certification, you just passed a single “CCNA exam.” With this
latest generation of the CCNA, you can either take a single exam to get your CCNA, or you
can take two exams, with each of these exams covering a subset of the CCNA exam topics.
Table I-1 lists the exams.
So, you either take the CCNA exam or you take both the INTRO and the ICND exam to
pass CCNA.
Like most Cisco certification exams, the names of the INTRO and the ICND exams come
from two Cisco Authorized courses. Cisco’s INTRO course covers a broad range of topics,
from Ethernet cabling to virtual private networks (VPNs). The Interconnecting Cisco
Network Devices (ICND) course dives more deeply into core Cisco technology and
protocols, in particular, switching and routing. Whereas the INTRO course covers a broader
range of topics to a small amount of depth, the ICND course covers fewer topics but to more
depth. Like their namesakes, the INTRO and ICND exams cover similar depth and breadth.
The CCNA exam simply covers everything on both the INTRO and ICND exams. So, if you
want to save some cash and you are confident that you are ready to answer questions across
the whole range of topics for CCNA, you can take just the CCNA exam itself. Alternately,
you can focus on the INTRO exam first, master those topics, pass the exam, and then move

on to the ICND exam.
Table I-1
CCNA Exam Names and Numbers
Exam Name
Exam
Number Comment
Introduction to Cisco Networking
Technologies (INTRO) exam
640-821 A subset of the CCNA topics; should be
taken before the ICND exam
Interconnecting Cisco Network
Devices (ICND) Exam
640-811 A subset of the CCNA topics; should be
taken after the INTRO exam
CCNA Exam 640-801 Can be taken instead of INTRO and
ICND exams; covers the same content
as the other two exams combined
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xix
Format of the CCNA Exams
The INTRO, ICND, and CCNA exams all follow the same general format. When you get to
the testing center and check in, the proctor will give you some general instructions and then
take you into a quiet room with a PC. When you’re at the PC, you have a few things to do
before the timer starts on your exam—for instance, you can take a sample quiz, just to get
accustomed to the PC and to the testing engine. Anyone who has user-level skills in getting
around a PC will have no problems with the testing envinronment.
When you start the exam, you will be asked a series of questions. You answer the question
and then move on to the next question. The exam engine does not let you go back and change
your answer. Yes, that’s true—when you move on to the next question, that’s it for the earlier
question.

The exam questions can be in the following format:
■
Multiple choice
■
Fill-in-the-blank
■
Drag-and-drop
■
Simulated lab
The multiple choice format simply requires that you point and click on a circle beside the
correct answer(s). If more than one answer is required, the questions traditionally have told
you how many answers to choose. Fill-in-the-blank questions require that you type in the
answer, so you must get the answer exactly correct.
Drag-and-drop questions require you to left-click and hold, move a button or icon to another
area, and release the clicker to place the object somewhere else—typically into a list. So, for
some questions, to get the question correct, you might need to put a list of five things into
the proper order.
Finally, the type of question that gives most people a scare before the exam is the simulated
lab question. The exam engine actually gives you an interface into a network with several
routers, and you must log in and troubleshoot a scenario. To solve the problem, you need to
be able to navigate through the user interface, know several commands, and possibly
configure something that has been misconfigured. You should also save your configurations,
unless the question tells you not to save it, just in case.
The best way to prepare for simulated lab questions is to practice with real gear. You can
actually find sites where CCNA lab access is free over the Internet—I did a search from
www.google.com tonight, searching for “free CCNA labs,” and the first three hits were
(seemingly) legitimate offers for free lab access for CCNA study. You can also use a simulator
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product, such as Cisco Press’s CCNA Router and Switch eSIM. A special version of Boson’s

Netsim product, compiled specifically for this book, is also included on the CD that comes
with this book.
What’s on the CCNA Exam(s)?
Ever since I was in grade school, whenever the teacher announced that we were having a test
soon, someone would always ask, “What’s on the test?” Even in college, people would try to
get more infomrmation about what would be on the exams. At heart, the goal is to know
what to study hard, what to study a little, and what to not study at all.
Cisco does want you to know what topics to study and wants you to be well prepared for
your exams. However, Cisco does not want to be so specific that you could just memorize a
certain set of facts and pass the exams. In short, Cisco wants you to pass the exams because
you know your stuff, not because you memorized a set of questions that someone posted
(possibly illegally) on an Internet site.
So, what can be said about the content of the exams? First, Cisco posts exam topics for each
exam. This official posting is the basis for what Cisco intends to put on the exams, so you
should pay particularly close attention to this list. Also, the breadth and depth of topics on
the exams tend to match the Cisco Authorized courses with which they are associated, so it
is useful to know the outlines for those courses. Finally, Cisco designs the Cisco Networking
Academy Program (CNAP) course materials with CCNA in mind. Looking at all these
sources can help give you insight into CCNA.
INTRO Exam Topics
Carefully consider the exam topics posted by Cisco on its web site as you study, particularly
for clues as to how deeply you should know each topic. The exam topics use action words
that follow a quasi-standard called Bloom’s Taxonomy of the Cognitive Domain. Bloom’s
taxonomy defines a standard for word usage for when educators create objectives for
courses. Objectives written according to Bloom’s taxonomy define what the learner (student)
should be able to accomplish after taking the class. So, when you look at an exam topic, look
for the action word. If you want to see a description of Bloom’s taxonomy, search the
Internet, and you will find a lot of matches. My favorite quick list of terms is at

The action word in the exam topic gives you a good hint about the level of knowledge and

skill you will need to have before taking the exam. For instance, a course objective that uses
the word list as the action word then means that you should be able to list the features, but
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an action word such as configure means that you should know all the related configuration
commands and how to use them. Troubleshoot might mean that you need to know what all
the show and debug commands do for a particular topic.
So, what does Bloom’s taxonomy mean in terms of how you study for the exam? It means
that you should focus on the action words in the exam topics and make sure that you can do
those things for the stated topics. For instance, if an exam topic says something like
“Configure RIP,” then do not study just RIP concepts, but also study the configuration details
because the exam topic specifically tells you that you need to know how to perform
configuration.
In addition, Cisco adds a disclaimer that the posted exam topics for all of its certification
exams are guidelines. Cisco makes the effort to keep the exam questions within the confines
of the stated exam objectives, but doing this for every question and every exam is difficult.
Thus, you could see questions that fall outside both the scope and the depth implied by the
exam topics. However, if you follow the Cisco exam topic “guidelines,” you should have a
good understanding of the breadth and depth of topics on the exam.
Table I-2 lists the exam topics for the INTRO exam. You can find the ICND exam topics in
the Introduction to the CCNA ICND Exam Certification Guide and on www.cisco.com.
Note that although Cisco’s posted exam topics are not numbered, we do number them in the
Cisco Press Exam Certification Guide series for easier reference. Also note that Cisco has
historically changed exam topics without changing the exam number, so do not be alarmed
if small changes in the exam topics occur over time. When in doubt, go to www.cisco.com,
click Learning and Events, and select Career Certifications and Paths.
Table I-2
INTRO Exam Topics
Exam Topic
Reference Number Exam Topic

Design & Support
1 Use a subset of Cisco IOS commands to analyse and report network
problems
2 Use embedded layer 3 through layer 7 protocols to establish, test,
suspend or disconnect connectivity to remote devices from the router
console
3 Determine IP addresses
Implementation & Operation
4 Establish communication between a terminal device and the router
IOS, and use IOS for system analysis
5 Manipulate system image and device configuration files
continues
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Exam Topic
Reference Number Exam Topic
6 Perform an initial configuration on a router and save the resultant
configuration file
7 Use commands incorporated within IOS to analyse and report
network problems
8 Assign IP addresses
9 Describe and install the hardware and software required to be able to
communicate via a network
10 Use embedded data link layer functionality to perform network
neighbor discovery and analysis from the router console
11 Use embedded layer 3 through layer 7 protocols to establish, test,
suspend or disconnect connectivity to remote devices from the router
console
Technology
12 Demonstrate the mathematical skills required to work seamlessly

with integer decimal, binary and hexadecimal numbers and simple
binary logic (AND)
13 Define and describe the structure and technologies of computer
networks
14 Describe the hardware and software required to be able to
communicate via a network
15 Describe the physical, electrical and mechanical properties and
standards associated with optical, wireless and copper media used in
networks
16 Describe the topologies and physical issues associated with cabling
common LANs
17 Identify the key characteristics of common wide area networking
(WAN) configurations and technologies , and differentiate between
these and common LAN technologies.
18 Describe the purpose and fundamental operation of the internetwork
operating system (IOS)
19 Describe the role of a router in a WAN.
20 Identify the major internal and external components of a router, and
describe the associated functionality
21 Identify and describe the stages of the router boot-up sequence
22 Describe how the configuration register and boot system commands
modify the router boot-up sequence
Table I-2
INTRO Exam Topics (Continued)
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Exam Topic
Reference Number Exam Topic
23 Describe the concepts associated with routing, and the different
methods and protocols used to achieve it

24 Describe how an IP address is associated with a device interface, and
the association between physical and logical addressing
25 Employ IP addressing techniques
26 Compare and contrast collision and broadcast domains, and describe
the process of network segmentation
27 Describe the principles and practice of switching in an Ethernet
network
28 Explain how collisions are detected and handled in an Ethernet
system
29 Explain the fundamental concepts associated with the Ethernet media
access technique
30 Describe how the protocols associated with TCP/IP allow host
communication to occur
31 Describe the operation of the Internet Control Message Protocol
(ICMP) and identify the reasons, types and format of associated error
and control messages
32 Describe the principles and practice of packet switching utilizing the
Internet Protocol (IP)
33 Describe, compare and contrast network communications using two
examples of layered models (OSI and IETF)
34 Describe the fundamental concepts associated with transport layer
protocols, and compare the connectionless approach to transport
with the connection oriented one
35 List the major TCP/IP application protocols, and briefly define their
features and operation
36 Describe the operation of the major transport layer protocols TCP
and UDP and the interaction and carriage of application layer data
37 Perform an initial configuration on a switch and save the resultant
configuration file
Table I-2

INTRO Exam Topics (Continued)
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Cross-Reference Between Exam Topics and Book Parts
Table I-3 provides a cross-reference between the exam topics and the book parts in which
they are covered.
CCNA Exam Topics
Interestingly, the CCNA (640-801) exam topics posted by Cisco are not simply the
combination of the INTRO exam topics and the ICND exam topics. If you look closely, the
CCNA exam topics match more closely to the ICND exam topics than they do to the INTRO
exam topics.
So, for those of you planning to take the single CCNA exam, what does that mean? Well, for
practical purposes, the CCNA exam covers all the topics covered on both the INTRO and
ICND exams. However, the length of the CCNA exam does not allow Cisco to ask you about
Table I-3
INTRO Exam Topics Cross-Reference to Parts in the CCNA INTRO Exam Certification
Guide
Exam Topic Part Exam Topic Part
1 2, 3, 4 19 1, 5
2 2 20 2
3 4 21 2
4 2 22 2
5 2 23 4
6 2 24 4
7 2, 3, 4 25 4
8 2, 4 26 1, 3
9 2, 3, 4, 5 27 3
10 2, 4 28 1
11 4 29 1
12 4 30 1

13 1 – 5 31 4
14 1 - 5 32 1, 4
15 1 33 1
16 1, 3 34 1
17 1, 5 35 1
18 2 36 1
37 2
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every possible fact. So, you should expect the CCNA exam to include questions that cover
more advanced topics, many of which require that you know the more basic facts. For
instance, rather than ask a question about how to do binary math, which is specifically
mentioned for the INTRO exam topics, you might have to derive subnet numbers – which
requires you to use binary math. Another example: instead of describing LAN cabling, you
might have a question about troubleshooting a LAN topology, and need to decide if an
incorrect type of cable was used. So, while the exam topics do not exactly match up, but you
essentially need to know all the same concepts on both the INTRO and ICND exams in order
to succeed on the CCNA exam.
Table I-4 lists the CCNA exam topics at time of publication. As always, look to
www.cisco.com for the latest posted information about the CCNA, INTRO, and ICND
exams!
Table I-4
CCNA Exam Topics
Exam Topic
Reference Number Exam Topic
Planning and Design
1 Design a simple LAN using Cisco Technology
2 Design an IP addressing scheme to meet design requirements
3 Select an appropriate routing protocol based on user requirements
4 Design a simple internetwork using Cisco technology

5 Develop an access list to meet user specifications
6 Choose WAN services to meet customer requirements
Implementation and Operation
7 Configure routing protocols given user requirements
8 Configure IP addresses, subnet masks, and gateway addresses on
routers and hosts
9 Configure a router for additional administrative functionality
10 Configure a switch with VLANS and inter-switch communication
11 Implement a LAN
12 Customize a switch configuration to meet specified network
requirements
13 Manage system image and device configuration files
14 Perform an initial configuration on a router
15 Perform an initial configuration on a switch
16 Implement access lists
17 Implement simple WAN protocols
continues
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