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Trang 2Network+ 2005
In Depth
Tamara Dean
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Trang 4To Andrew, for everything
Trang 5Preface 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
Trang 6Chapter 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
Trang 7Common 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
Trang 8Chapter 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
Trang 9Routers 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
Trang 10Wireless 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
Trang 11Remote 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
Trang 12Internetworking 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
Trang 13Chapter 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
Trang 14Nslookup 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
Trang 15Chapter 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
Trang 16Security 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