Cisco Networking Academy Program CCNA 1 and 2 Companion Guide Third Edition Cisco Systems, Inc... Cisco Networking Academy Program CCNA 1 and 2 Companion Guide Third Edition Cisco System
Trang 1Cisco Networking Academy Program CCNA 1 and 2 Companion Guide Third Edition
Cisco Systems, Inc
Cisco Networking Academy Program
Cisco Press
201 West 103rd Street Indianapolis, Indiana 46290 USA
www.ciscopress.com
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Trang 2Cisco Networking Academy Program
CCNA 1 and 2 Companion Guide
Third Edition
Cisco Systems, Inc.
Cisco Networking Academy Program Copyright © 2003 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 inclu-sion of brief quotations in a review.
Printed in the United States of America 1 2 3 4 5 6 7 8 9 0 Library of Congress Cataloging-in-Publication Number: 2002116787 ISBN: 1-58713-110-2
First Printing June 2003
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.
Warning and Disclaimer
This book is designed to provide information about CCNA 1: Networking Basics and CCNA 2: Routers and Routing Basics of the Cisco Networking Academy Program CCNA course Every effort has been made to make this book as complete and as accurate as possible, but no war-ranty 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.
This book is part of the Cisco Networking Academy Program series from Cisco Press The products in this series support and complement the Cisco Networking Academy Program curriculum If you are using this book outside the Networking Academy program, then you are not preparing with a Cisco trained and authorized Networking Academy provider.
For information on the Cisco Networking Academy Program or to locate a Networking Academy,
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Trang 4Cisco Systems
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Overview Foreword xxv
Introduction xxvii
Part I CCNA 1: Networking Basics 3
Chapter 1 Introduction to Networking 5
Chapter 2 Networking Fundamentals 43
Chapter 3 Networking Media 115
Chapter 4 Cable Testing and Cabling LANs and WANs 183
Chapter 5 Ethernet Fundamentals 251
Chapter 6 Ethernet Technologies and Ethernet Switching 315
Chapter 7 TCP/IP Protocol Suite and IP Addressing 375
Chapter 8 Routing Fundamentals and Subnets 427
Chapter 9 TCP/IP Transport and Application Layer 477
Part II CCNA 2: Routers and Routing Basics 509
Chapter 10 WANs and Routers 511
Chapter 11 Router Fundamentals 553
Chapter 12 Router Configuration 587
Chapter 13 Learning About Neighboring and Remote Devices 621
Chapter 14 Managing Cisco IOS Software 645
Chapter 15 Routing and Routing Protocols 675
Chapter 16 Distance Vector Routing Protocols 711
Chapter 17 TCP/IP Error and Control Messages 761
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Trang 6Chapter 18 Basic Router Troubleshooting 787
Chapter 19 Intermediate TCP 815
Chapter 20 Access Control Lists 841
Part III Appendixes 877
Appendix A Structured Cabling 879
Appendix B Glossary of Key Terms 979
Appendix C Check Your Understanding Answer Key .1009
Index 1047
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Table of Contents Foreword xxv Introduction xxvii Part I CCNA 1: Networking Basics 3
Chapter 1 Introduction to Networking 5
The Fundamentals of Internet Connectivity 5
PC Basics 6
Electronic Components 7
PC Components 7
Motherboard Components 10
Desktop Versus Laptop 11
Network Interface Cards 12
NIC and Modem Installation 13
Overview of High-Speed and Dialup Connectivity 14
TCP/IP Configuration 15
Testing Connectivity with Ping 15
Web Browsers and Plug-Ins 16
Other Common Computer Applications 18
Binary Numbers 18
Binary Representation of Data 19
Bits, Bytes, and Measurement Terms 19
Base 10 Number System 21
Base 2 Number System 22
Base 16 Number System 23
Decimal-to-Binary Conversion 24
Binary-to-Decimal Conversion 26
Hexadecimal and Binary Conversion 28
Four-Octet Dotted-Decimal Representation of a 32-Bit Binary Number 30
Boolean Logic 30
IP Addresses and Subnet Masks 32
Summary 33
Key Terms 35
Check Your Understanding 39
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Trang 8Chapter 2 Networking Fundamentals .43
Networking Terminology 43
Data Networks .44
Computer Networking History 47
Network Protocols 49
Local-Area Networks (LANs) 49
Wide-Area Networks (WANs) 50
Metropolitan-Area Networks (MANs) .52
Specialized Networks Located Within the LAN 53
Virtual Private Networks 56
Digital Bandwidth 58
The Importance of Bandwidth 58
Analogies That Describe Digital Bandwidth 59
Digital Bandwidth Measurements 61
Bandwidth Limitations .61
Data Throughput 63
Data Transfer Calculation 64
Digital Bandwidth Versus Analog Bandwidth .66
Networking Models 67
Using Layers to Analyze Problems in a Flow of Materials 67
Using Layers to Describe Data Communication 68
The OSI Reference Model 69
OSI Layers and Functions 71
Peer-to-Peer Communications 72
DoD (TCP/IP) Model 74
Detailed Encapsulation Process 75
Networking Devices 78
Repeaters 79
Hubs 79
Network Interface Cards 81
Bridges 82
Layer 2 Switches 83
Routers 84
Voice, DSL, Cable Modem, and Optical Devices 86
Security Devices 89
Wireless Devices 91
Network Topologies 93
Bus Topology 95
Star and Extended-Star Topologies .95
Ring Topology 97
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Hierarchical Topology 98
Full-Mesh and Partial-Mesh Topologies 98
Logical Topology 99
Summary 100
Key Terms 103
Check Your Understanding 106
Chapter 3 Networking Media 115
Electricity Basics 115
Atoms and Molecules 115
Electrical Properties of Matter 117
Measuring Electricity 118
Voltage 119
Current 120
Wattage 120
Resistance and Impedance 120
Circuits 121
Copper Media 123
American Wire Gauge System 123
Twisted-Pair Cable 124
Shielded Twisted-Pair Cable 124
Unshielded Twisted-Pair Cable 125
Coaxial Cable 128
Cable Specification and Termination 130
Optical Media 133
The Electromagnetic Spectrum 134
The Ray Model of Light 135
The Law of Reflection 137
The Law of Refraction (Snell’s Law) 138
Total Internal Reflection 139
Fiber-Optic Cables 141
Multimode Fiber 144
Single-Mode Fiber 145
Cable Designs 146
Other Optical Networking Components 147
Signals and Noise in Optical Fiber 149
Installation, Care, and Testing of Optical Fiber 151
Wireless Communications 154
Wireless Data Communications 154
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Trang 10Wireless Signal 155
Radio Frequency Bands 157
Spread-Spectrum Technology 159
FHSS Versus DSSS 159
Wireless Networking 161
Wireless LAN Organization and Standards 161
Wireless Devices and Topologies 162
How Wireless LANs Communicate 165
Authentication and Association 166
The Radio Wave/Microwave Spectrum .168
Signals and Noise on a WLAN .169
Wireless Security 170
WEP .170
VPN, EAP, and LEAP 171
Summary 172
Key Terms 174
Check Your Understanding 176
Chapter 4 Cable Testing and Cabling LANs and WANs 183
Background for Studying Frequency-Based Cable Testing 184
Waves .184
Sine Waves and Square Waves 185
Exponents and Logarithms .186
Decibels 187
Viewing Signals in Time and Frequency .188
Noise in Time and Frequency 189
Analog and Digital Bandwidth 190
Signals and Noise on Networking Media 191
Signaling over Copper and Fiber-Optic Cabling 192
Attenuation and Insertion Loss on Copper Media 195
Source of Noise on Copper Media 196
Cable Testing Standards 199
Other Test Parameters 202
Time-Based Parameters 202
Testing Fiber-Optic Cables 203
A New Cabling Standard 204
Cabling the LANs 205
LAN Physical Layer 205
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