数据通信与网络技术（第2版）

TABLE OF
CONTENTS
Preface xxvii
Chapter 1 Introduction l
l.1 WHY STUDY DATA COMMUNICAmONS I
1.2 DATA COMMUNICAmON 2
Components 3
l.3 NETWORKS 4
Distributed Processing 4
Network Criteria 5
Applications 6
1.4 PROTOCOLS AND STANDARDS 7
hotocols 7
Standards 8
1.5 STANDARDS ORGANIZATIONS 9
Standards Creation CommiHees 9
Fomms 12
Regulatory Agencies I 3
l.6 STRUCTURE OF THE BOOK 13
1.7 KEY TERMS AND CONCEPfS l 3
1.8 SUMMARY 14
l.9 PRACTICE SET 15
Review Questions l5
Multiple Choice Questions 16
Exercises 18
Chapter 2 Basic ConceIYts 21
2.1 LINE CONFIGURATION 2 I
Point-to-Point 21
Multipoint 22
2.2 TOPOLOOY 22
Mesh 23
Star 25
Tree 25
Bus 26
Ring 27
Hybrid Topologies 28
2.3 TRANSMISSION MODE 28
Simplex 29
Half-Duplex 29
Full-Duplex 29
2.4 CATEGORIES OF NETWORKS 30
Local Area Network LAN 30
Metropolitan Area Network MAN 32
Wide Area Network WAN 32
2.5 INTERNETWORKS 33
2.6 KEY TERMS AND CONCEPfS 34
2.7 SUMMARY 34
2.8 PRACTICE SET 35
Review Questions 35
Multiple Choice Qaestions 36
Exercises 38
Chapter 3 The OSI Model 43
3.l THE MODEL 43
Layered Architectare 43
3.2 FUNCTIONS OF THE LAYERS 47
Physical Layer 47
Data Link Layer 48
Network Layer 49
TranspoH Layer 50
Session Layer 53
Presentation Layer 54
Application Layer 55
Summary of Layer Functions 56
3.3 TCPnP PROTOCOL SUITE 56
3.4 KEY TERMS AND CONCEPfS 57
3.5 SUMMARY 58
3.6 PRACTICE SET 59
Review Questions 59
Multiple Choice Questions 59
Exercises 63
Chapter 4 Signals 65
4.1 ANALOG AND DIGITAL 65
Analog and Digital Data 66
Analog and Digital Signals 66
4.2 PERIODIC AND APERIODIC SIGNALS 66
Periodic Signals 67
Aperiodic Signals 67
4.3 ANALOG SIGNALS 68
Simple Analog Signals 68
4.4 TIME AND FREQUENCY DOMAINS 73
4.5 COMPOSITE SIGNALS 75
Frequency Spectrum and Bandwidth 76
4.6 DIGITAL SIGNALS 79
Decomposition of a Digital Signal 80
4.7 KEY TERMS AND CONCEPTS 8 l
4.8 SUMMARY 82
4.9 PRACmCE SET 83
Review Questions 83
Multiple Choice Questions 84
Exercises 87
Chapter 5 Encoding and Modulating 91
5.1 DIGITAL-TO-DIGITAL CONVERSION 92
Unipolar 92
Polar 94
Bipolar 97
5.2 ANALOC-TO-DIGITAL CONVERSION l02
Pulse Amplitude Modulation PAM 102
Pulse Code Modulation PCM 103
Sampling Rate 104
How Many Bits per Sample 106
Bit Rate 107
5.3 DIGITAL-TO-ANALOG CONVERSION 107
Aspects of Oigital-to-Analog Conversion 108
Amphtude Shift Keying ASK
Frequency ShiR Keying FSK
Rlase Shin Keying PSK
Quadrature Amplitude Modulation QAM
Bit/Baud Comparison
5.4 ANALOG-TO-ANALOG CONVERSION l20
Amplitude Modulation AM l21
Frequency Modulation Flvl l22
Phase Modulation PM l25
5.5 KEY TERMS AND CONCEPfS 125
5.6 SUMMARY l26
5.7 PRACTICE SET 127
Review Questions 127
Multiple Choice Questions 128
Exercises l33
Chapter 6 Transmlssion ofDigital Data: Interfaces and
Modems l39
6.1 DIGITAL DATA TRANSMISSION l39
Parallel Transmission 140
Serial Transmission 14l
6.2 DTE-DCE INTERFACE 143
Data Terminal Equipment DTE 144
Data Circuit-Terminating Equipment DCE 144
Standards l45
EIA-232 Interface 145
6.3 OTHER INTERFACE STANDARDS l52
EIA-449 l53
EIA-530 l57
X.21 158
6.4 MODEMS 159
Transmission Rate 160
Modem Standards 164
6.5 56K MODEMS 171
Traditional Modems l71
56K Modems 172
Why Only 56 Kbps 174
6.6 CABLE MODEM 174
Downloading l74
Uploading 175
6.7 KEY TERMS AND CONCEPfS 175
6.8 SUMMARY 176
6.9 PRACTICE SET l77
Review Questions l77
Multiple Choice Questions 179
Exercises 185
Chapter 7 Transmission Aledia 187
7.1 GUIDED MEDIA 188
Twisted-Pair Cable 188
Coaxial Cable 192
Optical Fiber 193
7.2 UNGUIDED MEDIA 200
Radio Frequency Allocation 200
hopagation of Radio Waves 200
Tenestrial Microwave 205
Satellite Communication 206
Cellular Telephony 208
7.3 TRANSMISSION IMPAIRMENT 2ll
Attenuation 211
Distortion 213
Noise 213
7.4 PERFORMANCE 2l4
Throughput 214
Propagation Speed 215
Propagation Time 215
7.5 WAVELENGTH 215
7.6 SHANNON CAPACITY 216
7.7 MEDIA COMPARISON 217
7.8 KEY TERMS AND CONCEPTS 218
7.9 SUMMARY 220
7.1O PRACTICE SET 222
Review Questions 222
Multiple Choice Questions 223
Exercises 230
Chapter 8 Alutiplexing 231
8.l MANY TO ONE/ONE TO MANY 23 I
8.2 FREQUENCY-DIVISION MULTIPLEXING FDM 232
8.3 WAVE-DIVISION MULTIPLEXING WDM 235
8.4 TIME-DIVISION MULTIPLEXING TDM 236
Inverse Multiplexing 244
8.5 MULTIPLEXING APPLICATION: THE TELEPHONE SYSTEM 245
Common CaITier Services alld Hierarchies 245
Analog Services 246
Digital Services 248
8.6 DIGITAL SUBSCRIBER LINE DSL 254
ADSL 254
RADSL 255
HDSL 2se
SDSL 256
VDSL 256
8.7 FTTC 257
FTTC in the Telephone Network 257
FTTC in the Cable TV Network 257
8.8 KEY TERMS AND CONCEPfS 258
8.9 SUMMARY 259
8.1O PRACTICE SET 261
Review Questions 261
Multiple Choice Questions 262
Exercises 266
Chapter 9 Error Detection and Correction 273
9.1 TYPES OF ERRORS 273
Single-Bit Error 273
Burst Error 274
9.2 DETECTION 275
Redundancy 275
9.3 VERTICAL REDUNDANCY CHECK VRC 277
9.4 LONGITUDINAL REDUNDANCY CHECK LRC 279
9.5 CYCLIC REDUNDANCY CHECK CRC 280
Performance 284
9.6 CHECKSUM 284
9.7 ERROR CORRECTION 287
Single-Bit Error Correction 287
Hamming Code 289
Burst Error Correction 291
9.8 KEY TERMS AND CONCEPTS 292
9.9 SUMMARY 293
9.1O PRACTICE SET 294
Review Questions 294
Multiple Choice Questions 294
Exercises 298
Chapter 1O Data Link Control 301
l0.1 LINE DISCIPLINE 302
ENQ/ACK 302
Poll/Select 304
1O.2 FLOW CONTROL 306
Stop-and-Wait 308
Sliding Window 30S
1O.3 ERROR CONTROL 312
Automatic Repeat Request ARQ 312
Stop-and-Wait ARQ 312
Sliding Window ARQ 315
1O.4 KEY TERMS AND CONCEPfS 321
1O.5 SUMMARY 32l
1O.6 PRACTICE SET 322
Review Questions 322
Multiple Choice Questions 323
Exercises 326
Chapter 11 Data Link Protocols 329
ll.1 ASYNCHRONOUS PROTOCOLS 330
XMODEM 330
YMODEM 331
ZMODEM 331
BLAST 331
Kermit 331
ll.2 SYNCHRONOUS PROTOCOLS 332
l1.3 CHARACTER-ORIENTED PROTOCOLS 332
Binary Synchronous Communication BSC 333
BSC Frames 334
Data Transparency 337
11.4 BIT-ORIENTED PROTOCOLS 339
HDLC 340
Frames 342
More about Frames 349
Examples 353
11.5 LINK ACCESS PROCEDURES 357
LAPB 357
LAPD 358
LAPM 358
11.6 KEY TERMS AND CONCEPTS 358
l1.7 SUMMARY 359
ll.8 PRACTICE SET 360
Review Questions 360
Multiple Choice Questions 361
Exercises 364
Chapter 12 Local Area Nenvorks 369
12.l PROJECT 802 369
IEEE 802. l 370
LLC 37 l
MAC 371
Protocol Data Unit PDU 371
l2.2 ETf$RNET 372
Access Method: CSMA/CD 373
Addressing 374
Electrical Specification 374
Frame Format 374
Implementation 376
l2.3 OTHER ETHERNET NETWORKS 380
Switched Ethernet 380
Fast Ethernet 382
Gigabit Ethernet 384
12.4 TOKEN BUS 385
12.5 TOKEN RINO 386
Access Method: Token Passing 386
Addressing 388
Electrical Specification 388
Frame Formats 388
Implementation 391
12.6 FDDI 393
Access Method: Token Passing 393
Addressing 395
Elecuical Specification 396
Franle Format 397
Implementation: Physical Medium Oependent PMD Layer 399
12.7 COMPARISON 401
12.8 KEY TERMS AND CONCEPfS 401
l2.9 SUMMARY 402
12.1O PRACTICE SET 404
Review Questions 404
Multiple Choice Qaestions 405
Exercises 409
Chapter 13 Metropolitan Area Networks 413
13.1 IEEE 802.6 DQDB 413
Access Method: Dual Bus 413
Distributed Queues 416
Ring Configuration 418
Operation: DQDB Layers 419
Implementation 420
13.2 SMDS 421
SMDS Architecture 421
Features 423
13.3 KEY TERMS AND CONCEPfS 424
l3.4 SUMMARY 424
l3.5 PRACTICE SET 425
Review Questions 425
Multiple Choice Questions 425
Exercises 427
Chapter 14 Switching 431
14.l CIRCUIT SWITCHING 432
Space-Division Switches 434
Time-Division Switches 436
TDM Bus 43S
Space- and Time-Division Switching Combinations 439
Public Switched Telephone Network PSTN 440
14.2 PACICET SWITCHING 441
Datagram Approach 442
ViHual Circuit Approach 443
Circuit-Switched Connection versus Vinual-Circuit Connection 444
14.3 MESSAGE SWITCHING 446
14.4 KEY TERMS AND CONCEPTS 447
14.5 SUMMARY 448
14.6 PRACTICE SET 449
Review Questions 449
Multiple Choice Questions 450
Exercises 452
Chapter 15 Point-to-Point Protocol PPP 455
15.1 TRANSITION STATES 455
15.2 PPP LAYERS 456
Physical Layer 456
Data Link Layer 457
l5.3 LINK CONTROL PROTOCOL LCP 458
LCP Packets 458
Options 460
l5.4 AUTHENTICATION 460
PAP 460
CHAP 461
15.5 NETWORK CONTROL PROTOCOL NCP 462
IPCP 463
Other Protocols 464