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To Andrew, for everything
Contents
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxii
Photo Credits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xxiii
State of the Information Technology (IT) Field . . . . . . . . . . . . . . . . . . xxv
Chapter 1 An Introduction to Networking . . . . . . . . . . . . . 1
Why Use Networks? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Types of Networks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Peer-to-peer Networks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Client/Server Networks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
LANs, MANs, and WANs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Elements Common to Client/Server Networks . . . . . . . . . . . . . . . . . . . . 9
How Networks Are Used . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
File and Print Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Communications Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Mail Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Internet Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Management Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Becoming a Networking Professional . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Mastering the Technical Challenges . . . . . . . . . . . . . . . . . . . . . . . . 17
Developing Your “Soft Skills” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Pursuing Certification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Finding a Job in Networking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Joining Professional Associations . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Key Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Chapter 2 Networking Standards and the OSI Model . . . 31
Networking Standards Organizations . . . . . . . . . . . . . . . . . . . . . . . . . . 32
ANSI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
EIA and TIA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
IEEE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
ISO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
ITU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
ISOC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
IANA and ICANN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
The OSI Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Application Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Presentation Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Session Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Transport Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Network Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Data Link Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Physical Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Applying the OSI Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Communication Between Two Systems . . . . . . . . . . . . . . . . . . . . . . 48
Frame Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
IEEE Networking Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Key Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Chapter 3 Transmission Basics and Networking Media . . 63
Transmission Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Analog and Digital Signaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Data Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Transmission Direction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Relationships Between Nodes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Throughput and Bandwidth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Baseband and Broadband . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Transmission Flaws . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Contents v
Common Media Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Throughput . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Cost . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Size and Scalability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Connectors and Media Converters . . . . . . . . . . . . . . . . . . . . . . . . . 81
Noise Immunity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Coaxial Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Twisted-Pair Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

STP (Shielded Twisted-Pair) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
UTP (Unshielded Twisted-Pair) . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Comparing STP and UTP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
10BASE-T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
100BASE-T (Fast Ethernet) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
1000BASE-T (Gigabit Ethernet over Twisted-pair) . . . . . . . . . . . . 93
1000BASE-CX (Gigabit Ethernet over Twinax) . . . . . . . . . . . . . . . 93
Fiber-Optic Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
SMF (Single-Mode Fiber) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
MMF (Multimode Fiber) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
10BASE-FL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
100BASE-FX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
1000BASE-LX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
1000BASE-SX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
10-Gigabit Fiber-Optic Standards . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Cable Design and Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
Installing Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
Wireless Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
The Wireless Spectrum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
Characteristics of Wireless Transmission . . . . . . . . . . . . . . . . . . . . 110
Infrared Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Wireless LAN (WLAN) Architecture . . . . . . . . . . . . . . . . . . . . . . 115
Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Key Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
vi Contents
Chapter 4 Network Protocols . . . . . . . . . . . . . . . . . . . . 135
Introduction to Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
TCP/IP (Transmission Control Protocol/Internet Protocol) . . . . . . . . 137
The TCP/IP Core Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

Addressing in TCP/IP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
Assigning IP Addresses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
Sockets and Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
Addressing in IPv6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160
Host Names and DNS (Domain Name System) . . . . . . . . . . . . . . 161
Some TCP/IP Application Layer Protocols . . . . . . . . . . . . . . . . . . 169
IPX/SPX (Internetwork Packet Exchange/Sequenced Packet
Exchange) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
The IPX and SPX Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
Addressing in IPX/SPX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
NetBIOS and NetBEUI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
Addressing in NetBEUI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177
WINS (Windows Internet Naming Service) . . . . . . . . . . . . . . . . . 177
AppleTalk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178
Binding Protocols on a Windows XP Workstation . . . . . . . . . . . . . . . 179
Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180
Key Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183
Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
Chapter 5 Networking Hardware. . . . . . . . . . . . . . . . . . 193
NICs (Network Interface Cards) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
Types of NICs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195
Installing NICs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
Repeaters and Hubs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Bridges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218
Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221
Installing a Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
Cut-Through Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224
Store and Forward Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225
Using Switches to Create VLANs . . . . . . . . . . . . . . . . . . . . . . . . . 225
Higher-Layer Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227

Contents vii
Routers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
Router Features and Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . 228
Routing Protocols: RIP, OSPF, EIGRP, and BGP . . . . . . . . . . . . . 231
Brouters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
Gateways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234
Key Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237
Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243
Chapter 6 Topologies and Access Methods . . . . . . . . . 245
Simple Physical Topologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
Bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
Ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
Star . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249
Hybrid Physical Topologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250
Star-Wired Ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250
Star-Wired Bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251
Backbone Networks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
Serial Backbone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
Distributed Backbone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
Collapsed Backbone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254
Parallel Backbone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 255
Logical Topologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256
Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257
Circuit Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257
Message Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
Packet Switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
Ethernet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259
CSMA/CD (Carrier Sense Multiple Access with Collision
Detection) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259

Switched Ethernet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261
Ethernet Frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262
PoE (Power over Ethernet) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264
Token Ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265
FDDI (Fiber Distributed Data Interface) . . . . . . . . . . . . . . . . . . . . . . 267
ATM (Asynchronous Transfer Mode) . . . . . . . . . . . . . . . . . . . . . . . . . 268
viii Contents
Wireless Networks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270
802.11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270
Bluetooth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275
Infrared (IR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277
Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 280
Key Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282
Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 288
Chapter 7 WANs, Internet Access, and Remote
Connectivity . . . . . . . . . . . . . . . . . . . . . . . . 291
WAN Essentials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 292
WAN Topologies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
Bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
Ring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
Star . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
Mesh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297
Tiered . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297
PSTN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299
X.25 and Frame Relay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 302
ISDN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305
T-Carriers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307
Types of T-Carriers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308
T-Carrier Connectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 309
DSL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 312

Types of DSL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 312
DSL Connectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314
Broadband Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 316
SONET (Synchronous Optical Network) . . . . . . . . . . . . . . . . . . . . . . 318
Wireless WANs and Internet Access . . . . . . . . . . . . . . . . . . . . . . . . . . 321
IEEE 802.11 Internet Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321
IEEE 802.16 (WiMAX) Internet Access . . . . . . . . . . . . . . . . . . . 323
Satellite Internet Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324
WAN Technologies Compared . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 327
Contents ix
Remote Connectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 328
Dial-up Networking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 328
Remote Access Servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329
Remote Access Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
Remote Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332
Terminal Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335
Web Portals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 336
VPNs (Virtual Private Networks) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 336
Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 338
Key Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 342
Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 351
Chapter 8 Network Operating Systems and Windows
Server 2003-Based Networking . . . . . . . . . . 355
Introduction to Network Operating Systems . . . . . . . . . . . . . . . . . . . . 356
Selecting a Network Operating System . . . . . . . . . . . . . . . . . . . . . 357
Network Operating Systems and Servers . . . . . . . . . . . . . . . . . . . . 358
Network Operating System Services and Features . . . . . . . . . . . . . . . . 359
Client Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 360
Identifying and Organizing Network Elements . . . . . . . . . . . . . . . 365
Sharing Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 368

Sharing Printers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 370
Managing System Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 372
Introduction to Windows Server 2003 . . . . . . . . . . . . . . . . . . . . . . . . 375
Windows Server 2003 Hardware Requirements . . . . . . . . . . . . . . . . . . 377
A Closer Look at Windows Server 2003 . . . . . . . . . . . . . . . . . . . . . . . 378
Windows Server 2003 Memory Model . . . . . . . . . . . . . . . . . . . . . 378
Windows Server 2003 File Systems . . . . . . . . . . . . . . . . . . . . . . . . 380
MMC (Microsoft Management Console) . . . . . . . . . . . . . . . . . . . 382
Active Directory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 384
Planning for Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 392
Installing and Configuring a Windows Server 2003 Server . . . . . . . . . 395
The Installation Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395
Initial Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 397
Establishing Users and Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . 399
x Contents
Internetworking with Other Network Operating Systems . . . . . . . . . . 402
Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 403
Key Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 405
Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 412
Chapter 9 Networking with UNIX-Type of Operating
Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . 415
A Brief History of UNIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 416
Varieties of UNIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 417
Proprietary UNIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 418
Open Source UNIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 418
Three Flavors of UNIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419
UNIX Server Hardware Requirements . . . . . . . . . . . . . . . . . . . . . . . . 420
Solaris Hardware Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . 421
Linux Hardware Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . 422
Mac OS X Server Hardware Requirements . . . . . . . . . . . . . . . . . . 423

A Closer Look at UNIX . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 423
UNIX Multiprocessing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 424
The UNIX Memory Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 424
The UNIX Kernel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 424
UNIX System File and Directory Structure . . . . . . . . . . . . . . . . . . 425
UNIX System File Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 426
A UNIX Command Sampler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 426
Installing Linux . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 432
Planning a Linux Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 432
Installing and Configuring Fedora Core . . . . . . . . . . . . . . . . . . . . 433
Administering a UNIX-Type of Server . . . . . . . . . . . . . . . . . . . . . . . . 434
Establishing Groups and Users on Linux and Solaris . . . . . . . . . . . 434
Establishing Groups and Users on Mac OS X Server . . . . . . . . . . . 435
Changing File Access Permissions . . . . . . . . . . . . . . . . . . . . . . . . . 438
Connecting to UNIX-Type of Servers . . . . . . . . . . . . . . . . . . . . . . 440
Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 442
Key Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 445
Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 447
Contents xi
Chapter 10 NetWare-Based Networking . . . . . . . . . . . . . 451
Introduction to NetWare . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 452
NetWare Server Hardware Requirements . . . . . . . . . . . . . . . . . . . . . . 455
A Closer Look at the NetWare 6.5 Operating System . . . . . . . . . . . . . 456
NetWare Integrated Kernel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 456
NetWare File System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 458
eDirectory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 460
Planning for Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 464
Installing and Configuring a NetWare 6.5 Server . . . . . . . . . . . . . . . . 466
The Installation Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 466
Establishing Users and Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . 468

Client Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 471
Traditional Client Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 471
Native File Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 472
Browser-Based Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 474
Internetworking with Other Operating Systems . . . . . . . . . . . . . . . . . 474
Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 475
Key Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 477
Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 479
Chapter 11 In-Depth TCP/IP Networking . . . . . . . . . . . . 481
Designing TCP/IP-Based Networks . . . . . . . . . . . . . . . . . . . . . . . . . . 482
Subnetting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 483
CIDR (Classless Inter-Domain Routing) . . . . . . . . . . . . . . . . . . . 491
Internet Gateways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 493
NAT (Network Address Translation) . . . . . . . . . . . . . . . . . . . . . . . 494
ICS (Internet Connection Sharing) . . . . . . . . . . . . . . . . . . . . . . . . 496
Intranets and Extranets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 497
TCP/IP Mail Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 498
SMTP (Simple Mail Transfer Protocol) . . . . . . . . . . . . . . . . . . . . . 498
MIME (Multipurpose Internet Mail Extensions) . . . . . . . . . . . . . 499
POP (Post Office Protocol) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499
IMAP (Internet Message Access Protocol) . . . . . . . . . . . . . . . . . . 500
Additional TCP/IP Utilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 501
Netstat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 502
Nbtstat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 503
xii Contents
Nslookup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 504
Dig . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 505
Whois . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 506
Traceroute (Tracert) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 507
Ipconfig . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 508

Winipcfg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 509
Ifconfig . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 510
VoIP (Voice Over IP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 511
Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 515
Key Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 517
Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 521
Chapter 12 Troubleshooting Network Problems . . . . . . . 523
Troubleshooting Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 524
Identify the Symptoms and Potential Causes . . . . . . . . . . . . . . . . . 525
Identify the Affected Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 526
Establish What Has Changed . . . . . . . . . . . . . . . . . . . . . . . . . . . . 530
Select the Most Probable Cause . . . . . . . . . . . . . . . . . . . . . . . . . . 531
Implement an Action Plan and Solution Including Potential Effects . .
537
Test the Result . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 541
Identify the Results and Effects of the Solution . . . . . . . . . . . . . . . 542
Document the Solution and Process . . . . . . . . . . . . . . . . . . . . . . . 542
Help to Prevent Future Problems . . . . . . . . . . . . . . . . . . . . . . . . . 545
Troubleshooting Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 546
Crossover Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 546
Tone Generator and Tone Locator . . . . . . . . . . . . . . . . . . . . . . . . . 546
Multimeter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 548
Cable Continuity Testers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 549
Cable Performance Testers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 551
Network Monitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 552
Protocol Analyzers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 554
Wireless Network Testers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 556
Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 558
Key Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 560
Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 563

Contents xiii
Chapter 13 Ensuring Integrity and Availability . . . . . . . . 565
What Are Integrity and Availability? . . . . . . . . . . . . . . . . . . . . . . . . . . 566
Viruses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 568
Types of Viruses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 569
Virus Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 571
Virus Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 572
Virus Hoaxes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 575
Fault Tolerance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 575
Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 576
Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 576
Topology and Connectivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 580
Servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 584
Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 587
Data Backup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 594
Backup Media and Methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 595
Backup Strategy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 598
Disaster Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 600
Disaster Recovery Planning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 601
Disaster Recovery Contingencies . . . . . . . . . . . . . . . . . . . . . . . . . . 601
Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 602
Key Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 606
Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 611
Chapter 14 Network Security. . . . . . . . . . . . . . . . . . . . . 615
Security Audits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 616
Security Risks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 617
Risks Associated with People . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 618
Risks Associated with Transmission and Hardware . . . . . . . . . . . . 619
Risks Associated with Protocols and Software . . . . . . . . . . . . . . . . 620
Risks Associated with Internet Access . . . . . . . . . . . . . . . . . . . . . . 621

An Effective Security Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 622
Security Policy Goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 622
Security Policy Content . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 624
Response Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 625
Physical Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 625
xiv Contents
Security in Network Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 627
Firewalls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 628
Proxy Servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 631
Remote Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 632
Network Operating System Security . . . . . . . . . . . . . . . . . . . . . . . . . . 633
Logon Restrictions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 634
Passwords . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 635
Encryption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 636
Key Encryption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 636
PGP (Pretty Good Privacy) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 641
SSL (Secure Sockets Layer) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 641
SSH (Secure Shell) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 642
SCP (Secure CoPy) and SFTP (Secure File Transfer Protocol) . . . 643
IPSec (Internet Protocol Security) . . . . . . . . . . . . . . . . . . . . . . . . . 644
Authentication Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 644
RADIUS and TACACS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 645
PAP (Password Authentication Protocol) . . . . . . . . . . . . . . . . . . . . 646
CHAP and MS-CHAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 646
EAP (Extensible Authentication Protocol) . . . . . . . . . . . . . . . . . . 649
Kerberos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 649
Wireless Network Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 651
WEP (Wired Equivalent Privacy) . . . . . . . . . . . . . . . . . . . . . . . . . 651
IEEE 802.11i and WPA (Wi-Fi Protected Access) . . . . . . . . . . . . 653
Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 653

Key Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 656
Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 664
Chapter 15 Implementing and Managing Networks. . . . . 667
Project Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 668
Determining Project Feasibility . . . . . . . . . . . . . . . . . . . . . . . . . . . 670
Assessing Needs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 671
Setting Project Goals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 672
Project Planning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 673
Testing and Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 677
Contents xv
Network Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 678
Obtaining Baseline Measurements . . . . . . . . . . . . . . . . . . . . . . . . . 678
Performance and Fault Management . . . . . . . . . . . . . . . . . . . . . . . 680
Asset Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 683
Software Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 684
Patches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 685
Client Upgrades . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 687
Shared Application Upgrades . . . . . . . . . . . . . . . . . . . . . . . . . . . . 688
Network Operating System Upgrades . . . . . . . . . . . . . . . . . . . . . . 689
Reversing a Software Upgrade . . . . . . . . . . . . . . . . . . . . . . . . . . . . 691
Hardware and Physical Plant Changes . . . . . . . . . . . . . . . . . . . . . . . . 692
Adding or Upgrading Equipment . . . . . . . . . . . . . . . . . . . . . . . . . 693
Cabling Upgrades . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 695
Backbone Upgrades . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 696
Reversing Hardware Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 697
Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 697
Key Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 700
Review Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 702
Appendix A Network+ Examination Objectives . . . . . . . . 705
Appendix B Network+ Practice Exam . . . . . . . . . . . . . . . 715

Appendix C Visual Guide to Connectors . . . . . . . . . . . . . 739
Appendix D Standard Networking Forms . . . . . . . . . . . . . 743
Appendix E Answers to Chapter Review Questions. . . . . 751
Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . 757
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 829
xvi Contents
Preface
K
nowing how to install, configure, and troubleshoot a computer network is a highly
marketable and exciting skill. This book first introduces the fundamental building
blocks that form a modern network, such as protocols, topologies, hardware, and network
operating systems. It then provides in-depth coverage of the most important concepts in
contemporary networking, such as client/server architecture, TCP/IP, Ethernet, wireless
transmission, and security. After reading the book, you will be prepared to select the best
network design, hardware, and software for your environment. You will also have the skills
to build a network from scratch and maintain, upgrade, and troubleshoot an existing net-
work. Finally, you will be well-prepared to pass CompTIA’s (the Computing Technology
Industry Association’s) Network+ certification exam.
Because some technical topics can be difficult to grasp, this book explains concepts logi-
cally and in a clear, approachable style. In addition, concepts are reinforced by real-world
examples of networking issues from a professional’s standpoint. The numerous tables and
illustrations, along with the glossaries, appendices, and study questions make the book a
valuable reference for any networking professional.
The Network+ CoursePrep Exam Guide, which you can download from
offers several hundred multiple choice questions to
further prepare you for passing CompTIA’s Network+ certification exam.
Intended Audience
This book is intended to serve the needs of students and professionals who are interested
in mastering fundamental, vendor-independent networking concepts. No previous net-
working experience is necessary to begin learning from this book, although knowledge of

basic computer principles is helpful. Those seeking to pass CompTIA’s Network+ certifi-
cation exam will find the text’s content, approach, and numerous study questions especially
helpful. For more information on Network+ certification, visit CompTIA’s web site at
www.comptia.org.
The book’s pedagogical features are designed to provide a truly interactive learning expe-
rience, preparing you for the challenges of the highly dynamic networking industry.
Chapter Descriptions
Here is a summary of the topics covered in each chapter of this book:
Chapter 1, “An Introduction to Networking,” begins by answering the question “What is
a network?” Next it presents the fundamental types of networks and describes the elements
that constitute the most popular type, the client/server network. This chapter also intro-
duces career options for those interested in mastering networking skills.
Chapter 2, “Networking Standards and the OSI Model,” describes the organizations that
set standards in the networking industry, including those that oversee wiring codes, net-
work access methods, and Internet addressing. It also discusses, in depth, the OSI Model,
which is the industry standard for conceptualizing communication between computers on
a network.
Chapter 3, “Transmission Basics and Networking Media,” describes signaling techniques
used on modern networks, including those used over copper cable, fiber-optic cable, and
wireless connections. It also covers the characteristics—including cost, materials, and con-
nector types—for physical and atmospheric media that can be used to carry signals.
Chapter 4, “Network Protocols,” explores network protocols in detail, with a particular
emphasis on the TCP/IP protocol suite. Functions and interactions between each core pro-
tocol and subprotocol are described in the context of the OSI Model. This chapter also
explains computer addressing and naming conventions for each major protocol suite.
Chapter 5, “Networking Hardware,” examines the hardware associated with a network,
including NICs (network interface cards), hubs, routers, bridges, gateways, and switches.
In Chapter 5, you will find several photos portraying typical networking equipment.
Chapters 6, “Topologies and Access Methods,” discusses the variety of physical and log-
ical topologies used in local area networks. This chapter includes detailed discussions of

the popular Ethernet and wireless access methods.
Chapter 7, “WANs, Internet Access, and Remote Connectivity,” expands on your knowl-
edge of networks by examining WAN (wide area network) topologies and transmission
methods, such as T-carriers, ISDN, DSL, and broadband cable. Here you will also learn
about options for accessing networks from remote locations, including dial-up network-
ing and VPNs (virtual private networks).
Chapter 8, “Network Operating Systems and Windows Server 2003-Based Networking,”
covers the purpose and design of network operating system software. It then provides an
overview of the Microsoft Windows Server 2003 network operating system, including
Active Directory, the Windows Server 2003 method of organizing network elements. In
this chapter you will also learn how to integrate Windows servers with clients and servers
running different operating systems.
xviii Preface
Chapter 9, “Networking with UNIX-type of Operating Systems,” discusses the unique
features of UNIX, Linux, and Mac OS X Server network operating systems (collectively
termed “UNIX-type of systems”). It enumerates basic commands that can be used on
UNIX-type of systems and explains how these operating systems can share resources and
communicate over networks.
Chapter 10, “NetWare-Based Networking,” describes the unique features of the Novell
NetWare network operating system, including eDirectory (or NDS), which is NetWare’s
method of organizing network elements. You will also learn how to integrate NetWare
servers with clients and servers running different operating systems.
Chapter 11, “In-Depth TCP/IP Networking,” explores advanced concepts relating to
TCP/IP-based networking, such as subnetting and NAT (Network Address Translation).
It also details commands useful for evaluating devices and connections that run the
TCP/IP protocol suite.
Chapter 12, “Troubleshooting Network Problems,” approaches the tasks of troubleshoot-
ing and maintaining networks in a logical, practical manner. Once you have learned how
networks operate and how to create them, you will need to know how to fix and maintain
them.

Chapter 13, “Ensuring Integrity and Availability,” explains how to keep network resources
available and connections reliable despite threats such as power outages or hardware and
software failures. In this chapter you will find information about backup power supplies,
redundant disk arrays, and data backup procedures.
Chapter 14, “Network Security,” discusses critical network security techniques, including
the use of firewalls, encryption, and enterprise-wide security policies. Network security is
a major concern when designing and maintaining modern networks, which typically use
open protocols and connect to public networks such as the Internet.
Chapter 15, “Implementing and Managing Networks,” concludes the book by describing
how to approach large network projects including software or hardware updates or an
entire network implementation. This chapter builds on all the knowledge you’ve gained
about network fundamentals, design, maintenance, and troubleshooting.
Appendix A, “Network+ Examination Objectives,” provides a complete list of the 2005
Network+ certification exam objectives, including the percentage of the exam’s content
they represent and which chapters in the book cover material associated with each objec-
tive.
Appendix B, “Network+ Practice Exam,” offers a practice exam containing questions sim-
ilar in content and presentation to those you will find on CompTIA’s Network+ exami-
nation.
Preface xix
Appendix C, “Visual Guide to Connectors,” provides a visual connector reference chart
for quick identification of connectors and receptacles used in contemporary networking.
Appendix D, “Standard Networking Forms,” gives examples of forms that you can use
while planning, installing, and troubleshooting your network.
Appendix E, “Answers to Chapter Review Questions,” provides the answers to the Review
Questions at the end of each chapter.
CoursePrep ExamGuide
Available for download from you will find PDF
files containing the Network+ CoursePrep ExamGuide. This certification prep workbook
provides the essential information you need to master each exam objective. The Exam-

Guide devotes an entire two-page spread to each certification objective from the Comp-
TIA Network+ exam, helping you understand the objective, and giving you the bottom
line information—what you really need to know. Memorize these facts and bulleted points
before heading into the exam. In addition, the ExamGuide includes seven practice-test
questions for each objective on the right-hand page. That’s more than 600 questions total!
You can find answers to all the practice test questions in the answer key at the end of the
ExamGuide, so that you can practice, drill, and rehearse for the exam.
Features
To aid you in fully understanding networking concepts, this book includes many features
designed to enhance your learning experience.
◆ Chapter Objectives. Each chapter begins with a list of the concepts to be mas-
tered within that chapter. This list provides you with both a quick reference to
the chapter’s contents and a useful study aid.
◆ Illustrations and Tables. Numerous full-color illustrations of network media,
methods of signaling, protocol behavior, hardware, topology, software screens,
peripherals, and components help you visualize common network elements, the-
ories, and concepts. In addition, the many tables included provide details and
comparisons of both practical and theoretical information.
◆ Chapter Summaries. Each chapter’s text is followed by a summary of the con-
cepts introduced in that chapter. These summaries provide a helpful way to
recap and revisit the ideas covered in each chapter.
◆ Review Questions. The end-of-chapter assessment begins with a set of review
questions that reinforce the ideas introduced in each chapter. Answering these
questions will ensure that you have mastered the important concepts and pro-
vide valuable practice for taking CompTIA’s Network+ exam.
xx Preface
Text and Graphic Conventions
Wherever appropriate, additional information and exercises have been added to this book
to help you better understand the topic at hand. The following icons are used throughout
the text to alert you to additional materials:

Preface xxi
The Note icon draws your attention to helpful material related to the subject
being described.
NOTE
Tips based on the author’s experience provide extra information about how to
attack a problem or what to do in real-world situations.
TIP
The caution icons draw your attention to warnings about potential problems and
explanations of how to avoid them.
CAUTION
All of the content that relates to CompTIA’s Network+ Certification exam, whether it’s a
page or a sentence, is highlighted with a Net+ icon and the relevant objective number.
This unique feature highlights the important information at a glance, so you can pay extra
attention to the certification material.
Acknowledgments
A
s with any large undertaking, this book is the result of many contributions and col-
laborative efforts. It would not exist without the help of friends, family, fellow net-
working professionals, and Thomson Course Technology staff. Thanks to Kristen Duerr,
Publisher and Executive Vice President, for her continued enthusiasm and support for the
project and to Will Pitkin, Managing Editor, for his dedication and business expertise.
I’m deeply grateful to Amy Lyon, Product Manager, for assembling a top-notch team and
maintaining enthusiasm, order, and a steady flow of communication that allowed the pro-
ject to advance smoothly. Many thanks to Ann Shaffer, Developmental Editor and friend,
for handling extreme deadlines with grace and for insisting on coherence, clarity, and pre-
cision throughout each draft. With this edition, I am again indebted to Elena Montillo,
Senior Production Editor, and Danielle Slade, Production Editor, who guided the book
from final edits to finished product. I’m grateful also to Christian Kunciw, Quality Assur-
ance Team Leader, and Marianne Snow, Quality Assurance tester—for scrutinizing every
page and alerting me to errors and inconsistencies. Thanks to Copy Editor Karen Annett,

whose close attention to details helped make the book clearer, consistent, and more pre-
cise. Thanks also to Abby Reip, who researched and obtained photos and permissions.
I’m especially grateful to Technical Editor Sydney Shewchuk who reviewed this edition
for technical accuracy and made many valuable suggestions for improvement.
For additional help and advice on technical topics, I’m grateful to networking profession-
als Jim Berbee, Tom Callaci, Peyton Engel, Michael Grice, Carla Schroeder, Tracy Syslo,
Lou Taber, and Ron Young. Special thanks to David Klann, UNIX disciple and con-
tributing author, who generously supplied content, helped with research, and was eager to
discuss the implications of non-contiguous subnetting on a Saturday night. Finally, thanks
again to Paul and Janet Dean, scientists and teachers both, for their encouragement, sup-
port, and continued interest in science and technology.
Photo Credits
Figure 1-5 © Gary Herrington Photography
Figure 2-6 Courtesy of 3Com Corporation
Figure 3-14 Courtesy of VERSITRON, Inc.
Figure 3-16 Courtesy of Stellar Labs (www.stellarlabs.com)
Figure 3-19 Courtesy of Belden, Inc.
Figure 3-21 © Gary Herrington Photography
Figure 3-24 Courtesy of Optical Cable Corporation
Figure 3-27a - d Courtesy of SENKO Advanced Components, Inc.
Figure 3-29 Courtesy of Siemon
Figure 3-30 Courtesy of Siemon
Figure 3-43 Courtesy of BlackBox Corporation
Figure 3-44 Courtesy of Belkin Corporation
Figure 3-45 Courtesy of Belkin Corporation
Figure 5-4 Courtesy of 3Com Corporation
Figure 5-5 Courtesy of PCMCIA
Figure 5-6 Courtesy of Linksys
Figure 5-7 Courtesy of TRT Business Network Solutions
Figure 5-8 Courtesy of Socket Communications

Figure 5-9 Courtesy of NETGEAR; Courtesy of SMC Networks, Inc.;
Courtesy of Belkin Corporation
Figure 5-10 © Gary Herrington Photography
Figure 5-11 © Gary Herrington Photography
Figure 5-15 Courtesy of 3Com Corporation
Figure 5-16 Courtesy of 3Com Corporation
Figure 5-19 Courtesy of 3Com Corporation; Courtesy of Nortel Networks
Figure 5-23 Courtesy of Enterasys Networks, Inc.; Courtesy of Enterasys
Networks, Inc.; Courtesy of NETGEAR
Figure 7-14 Courtesy of NETGEAR
Figure 7-16 Courtesy of Linksys
Figure 12-5 Courtesy of Agilent Technologies
Figure 12-6 Courtesy of Fluke Networks
Figure 12-7 Courtesy of Fluke Networks
Figure 12-8 Courtesy of Network Associates, Inc.
Figure 12-10 Courtesy of Fluke Networks
Figure 13-1 Courtesy of American Power Conversion Corporation
Figure 13-12 Courtesy of Imation
Figure 15-6 Redrawn with permission from SolarWinds.Net
xxiv Photo Credits