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San Francisco • London

Network+

™


ISBN: 0-7821-4014-9
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The logo of the CompTIA Authorized Quality Curriculum Program and the status of this or other training material as
“Authorized” under the CompTIA Authorized Curriculum Program signifies that, in CompTIA’s opinion, such training
material covers the content of the CompTIA’s related certification exam. CompTIA has not reviewed or approved the
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a particular purpose. CompTIA makes no guarantee concerning the success of persons using any such “Authorized” or other
training material in order to prepare for any CompTIA certification exam.
The contents of this training material were created for the CompTIA Network+ exam covering CompTIA certification exam
objectives that were current as of June 2001.
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How to Become CompTIA Certified
:
This training material can help you prepare for and pass a related CompTIA certification exam or exams. In order to achieve
CompTIA certification, you must register for and pass a CompTIA certification exam or exams.
In order to become CompTIA certified, you must:
• Select a certification exam provider. For more information, please visit

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CompTIA recently revised the Network+ exam, updating the objectives set, expanding the question
pool, and adding select-and-place questions formats, all in an effort to prevent the dreaded paper-
certification syndrome, one in which individuals obtain a certification without a thorough under-
standing of the technology. Sybex supports this philosophy, as we have always advocated a compre-
hensive instructional approach to certification courseware. It has always been Sybex’s mission to teach
exam candidates how new technologies work in the real world, not to simply feed them answers to test
questions.
We’re especially excited about this third edition of our best-selling

Network

+

Study Guide

, as it now
sports the new CompTIA Authorized Quality Curriculum (CAQC) logo on the cover. CompTIA
developed the CAQC program to help exam candidates make better decisions about which training
materials to use, and has established rigorous standards that courseware developers must meet in
order to display the CAQC logo. The book you hold in your hands went through a review process that
checked for exam objective correlation and instructional design integrity, and we are happy to say
that we passed with flying colors! We’re confident that this book will help you, the Network+ exam
candidate, succeed in your endeavors.
Good luck in pursuit of your Network+ certification!
Neil Edde
Associate Publisher—Certification
Sybex, Inc.
SYBEX Inc. 1151 Marina Village Parkway, Alameda, CA 94501
Tel: 510/523-8233 Fax: 510/523-2373 HTTP://www.sybex.com
Copyright ©2002 SYBEX, Inc., Alameda, CA

Rabinovitch.
I must also take a moment to recognize the unwavering good work of this
book’s technical editor, Andre Paree-Huff. He has faithfully watched over
this book from its first edition and is responsible for maintaining its accu-
racy. For each edition, including this one, a pool of top-notch technical edi-
tors helped out Andre by completing a second full technical edit just before
the book was sent to the printer. Bob Gradante, Jutta VanStean, and Louis
DiPaola should also be gratefully acknowledged for their fine expertise.
I would also like to recognize my wife, family, and friends. My wife,
Linda, tirelessly wrote and edited the appendices and kept me on the right
track. She was a real trooper because she managed to do that while watching
our daughter, Alison, who can be a handful. Thank you to my family and
friends who understood when I couldn’t go out or help them with projects
because I had to work on the book. I really appreciate that.
Finally, thank you, the reader, for purchasing this book. I know that
it has all the information in it to help you pass the test. If you have
questions about Network+ or this book, feel free to e-mail me at



. All of us involved in the
book project have worked very hard to make it the best Network+ Study
Guide available. I hope you feel the same.
Copyright ©2002 SYBEX, Inc., Alameda, CA
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Contents at a Glance

Introduction xx
Assessment Test xxxiii


Network Access and Security 347

Chapter 9

Fault Tolerance and Disaster Recovery 405

Chapter 10

Network Troubleshooting 455

Glossary

511

Index 558
Copyright ©2002 SYBEX, Inc., Alameda, CA
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Introduction

I

f you are like the rest of the networking community, you probably have
many certifications. Certification is one of the best things you can do for
your career in the computer or networking field. It proves that you know
what you’re talking about when it comes to the area in which you are
certified.
In this book, you’ll find out what the Network+ exam is all about. Each
chapter covers a part of the exam. At the end of each chapter, there are

Novell


TSS


U.S. Robotics


US West


Wave Technologies
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Introduction

xxi

The Network+ exam was designed to test the skills of network technicians
with 18 to 24 months of experience in the field. It tests areas of networking
technologies such as the definition of a protocol, the OSI (Open Systems
Interconnect) model and its layers, and the concepts of network design and
implementation—such as which items are required for a network and the
prerequisites for installation. In addition, it covers troubleshooting concepts
and how-tos.

Why Become Network+ Certified?


We all like to get ahead in our careers. With advancement comes more
responsibility, to be sure, but usually it means more money and greater
opportunities. In the information technology area, this usually can be
accomplished by obtaining multiple technology certifications, including
Network+.
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xxii

Introduction

Network+, because of its wide-reaching industry support, is recognized as
a baseline of networking information. Some companies specify that Net-
work+ certification will result in a pay raise at review time. And some com-
panies specify that Network+ certification, in conjunction with A+
certification, is required either before an employee’s next review or as a con-
dition of employment.

Fulfillment of Training Requirements

A training requirement can be mandated by your employer, as just men-
tioned, or it can be required as part of another certification. There has been
talk of using the Network+ certification as a prerequisite to, or as part of,
other vendors’ certifications. And I think it’s a natural fit. For example,
training for both the Novell and the Microsoft certification programs (CNE
and MCSE) includes a course in the essential networking technologies.
Because the Network+ exam covers network fundamentals and is vendor
neutral, it may be a good replacement for the Microsoft or the Novell exam.


Introduction

xxiii

Who Should Buy This Book?

I

f you are one of the many people who want to pass the Network+
exam, and pass it confidently, then you should buy this book and use it to
study for the exam. The Network+ exam is designed to measure the technical
knowledge of networking professionals with 18–24 months of experience in
the IT industry. This book was written with one goal in mind: not to just pre-
pare you for passing the Network+ exam, but to prepare to you for the chal-
lenges of the real IT world. This study guide will do that by describing in
detail the concepts on which you’ll be tested.

How to Use This Book and CD

T

his book includes several features that will make studying for
the Network+ exam easier. At the beginning of the book (right after this
introduction, in fact) is an assessment test that you can use to check your
readiness for the actual exam. Take this exam before you start reading
the book. It will help you to determine the areas you may need to “brush up”
on. You can then focus on these areas while reading the book. The answers
to this test appear on a separate page after the last question. Each answer
also includes an explanation and a note telling you in which chapter this
material appears.

pick a certain number of questions, and it will simulate the actual exam.
Combined, these test engine elements will allow you to test your readiness
for the real Network+ exam.

Full Text of the Book in PDF

If you are going to travel but still need to
study for the Network+ exam—and you have a laptop with a CD-ROM
drive—you can take this entire book with you on the CD-ROM. This
book is in PDF (Adobe Acrobat) format so it can be easily read on any
computer.

Exam Objectives

I

n this section, we are going to look at the objectives that the Network+
exam is designed to test. These objectives were developed by a group of
networking-industry professionals through the use of an industry-wide
job task analysis. CompTIA asked groups of IT professionals to fill out a
survey rating the skills they felt were important in their job. The results were
grouped into objectives for the exam. Each of these objectives is divided into
four domains. The following table indicates the extent to which they are
represented in the actual examination.
This section includes the outline of the exam objectives for the Network+
exam and the weighting of each objective category.

The objectives and weighting percentages given in this section can change at
any time. Check CompTIA’s website at


Bus


Mesh


Ring


Wireless
1.2 Specify the main features of 802.2 (LLC), 802.3 (Ethernet), 802.5
(Token Ring), 802.11b (wireless), and FDDI networking technologies,
including (3%):


Speed


Access


Method


Topology


Media
1.3 Specify the characteristics (e.g., speed, length, topology, cable
type, etc.) of the following (3%):

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xxvi

Introduction


AUI


BNC


ST


SC
1.5 Choose the appropriate media type and connectors to add a client
to an existing network. (3%)
1.6 Identify the purpose, features, and functions of the following
network components (5%):


Hubs


Switches


Bridges


TCP/IP


IPX/SPX
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Introduction

xxvii


NetBEUI


AppleTalk
2.4 Identify the OSI layers at which the following network compo-
nents operate (2%):


Hubs


Switches


Bridges




NTP
2.6 Define the function of TCP/UDP ports. Identify well-known ports.
(2%)
2.7 Identify the purpose of the following network services: DHCP/
bootp, DNS, NAT/ICS, WINS, and SNMP. (2%)
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xxviii Introduction
2.8 Identify IP addresses (Ipv4, Ipv6) and their default subnet masks.
(2%)
2.9 Identify the purpose of subnetting and default gateways. (2%)
2.10 Identify the differences between public vs. private networks.
(2%)
2.11 Identify the basic characteristics (e.g., speed, capacity, media) of
the following WAN technologies. (2%)

Packet switching vs. circuit switching

ISDN

FDDI

ATM

Frame relay

SONET/SDH

T1/E1

authentication, file and print services, application support, and
security) of the following server operating systems (4%):

Unix/Linux

NetWare

Windows

Macintosh
3.2 Identify the basic capabilities of client workstations (i.e., client
connectivity, local security mechanisms, and authentication).
3.3 Identify the main characteristics of VLANs. (2%)
3.4 Identify the main characteristics of network attached storage.
(2%)
3.5 Identify the purpose and characteristics of fault tolerance. (2%)
3.6 Identify the purpose and characteristics of disaster recovery. (2%)
3.7 Given a remote connectivity scenario (e.g., IP, IPX, dial-up,
PPPoE, authentication, physical connectivity, etc.), configure the
connection. (2%)
3.8 Identify the purpose, benefits, and characteristics of using a
firewall. (2%)
3.9 Identify the purpose, benefits, and characteristics of using a
proxy. (2%)
3.10 Given a scenario, predict the impact of a particular security
implementation on network functionality (e.g., blocking port
numbers, encryption, etc.). (2%)
3.11 Given a network configuration, select the appropriate NIC and
network configuration settings (DHCP, DNS, WINS, protocols,
NetBIOS/host name, etc.). (2%)

following servers (2%):

Unix/Linux

NetWare

Windows

Macintosh
4.5 Given a wiring task, select the appropriate tool (e.g., wire crimper,
media tester/certifier, punchdown tool, tone generator, optical tester,
etc.). (2%)
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Introduction xxxi
4.6 Given a network scenario, interpret visual indicators (e.g., link
lights, collision lights, etc.) to determine the nature of the problem.
(2%)
4.7 Given output from a diagnostic utility (e.g., tracert, ping, ipconfig,
etc.), identify the utility and interpret the output. (2%)
4.8 Given a scenario, predict the impact of modifying, adding, or
removing network services (e.g., DHCP, DNS, WINS, etc.) on
network resources and users. (2%)
4.9 Given a network problem scenario, select an appropriate course of
action based on a general troubleshooting strategy. This strategy
includes the following steps (4%):
1.
Establish the symptoms.
2.
Identify the affected area.

Get a good night’s sleep before the exam.

Bring two forms of ID with you. One form must be a photo ID, such
as a driver’s license. The other can be a major credit card or a passport.
Both forms must have a signature.

Take your time on each question. Don’t rush.

Arrive at the testing center a few minutes early so that you can review
your notes.

Answer all questions, even if you don’t know the answer. Unanswered
or blank questions are considered wrong. On-screen help allows you
to mark a question for answering later or reviewing a previous
question.

There will be questions with multiple correct responses. When there
are multiple correct answers, a message at the bottom of the screen
will prompt you to “choose all that apply.” Be sure to read the
messages.

Read the question twice and make sure you understand it.
Good luck on your Network+ exam and in your future in the IT industry.
Copyright ©2002 SYBEX, Inc., Alameda, CA
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Assessment Test for Network+ Exam
1.
Which TCP/IP utility can tell you which server is the mail server for the
domain foo.com?
A.

Firewall
4.
What is the proper name for the device that connects a PC to an ISDN
network?
A.
Hub
B.
Modem
C.
Switch
D.
Terminal Adapter
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xxxiv Assessment Test for Network+ Exam
5.
Which utility does not come with Windows 98?
A.
winipcfg
B.
tracert
C.
Ping
D.
ipconfig
6.
VLANs are a feature primarily of which type of network device?
A.
Hubs
B.

RIP
B.
OSPF
C.
NLSP
D.
RTMP
Copyright ©2002 SYBEX, Inc., Alameda, CA
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Assessment Test for Network+ Exam xxxv
10.
Which version is the most current Windows server operating system?
A.
Windows NT 3.51
B.
Windows NT 4.0
C.
Windows 2000
D.
Windows NT 6
11.
You are the network administrator for a small company. You come to
work one morning and find that the server fails to boot. When it does
boot, it has all kinds of configuration errors and data corruption. It
was fine yesterday when you left work. You remember that there was
a short power failure last night. What device would have prevented
these problems?
A.
Router
B.