CHAPTER 1 INTRODUCTION TO COMMUNICATIONS,STANDARDS,AND PROTOCOLS 1
1.1 VVHY STUDY COMMUNICATIONS? 1
A Brief History 1
Applications 3
Issues 6
1.2 COMPUTER NETWORKS 7
Common Bus Topology 9
StarTopology 10
Ring Topology 11
Fully Connected Topology 12
Combined Topologies 13
1.3 STANDARDS AND STANDARDS ORGANIZATIONS 14
The Need for Standards 14
Agencies 15
1.4 OPEN SYSTEMS AND THE OSI MODEL 17
Overview of the Model 20
Physical Layer 23
Data Link Layer 28
Network Layer 30
Transport Layer 32
Session Layer 38
Presentation Layer 42
Application Layer 45
Summary 46
1.5 THE FUTURE OF DATA COMMUNICATIONS 47
REVIEW QUESTIONS 51
EXERCISES 53
REFERENCES 54
CHAPTER 2 TRANSMISSION FUNDAMENTALS 56
2.1 COMMUNICATIONS MEDIA 57
Conductive Metal 59
Optical Fiber 62
Wireless Communications 66
Summary 81
Telephone System 83
2.2 COMMUNICATION SERVICES AND DEVICES 83
Integrated Services Digital Network 87
Cellular Phones 88
FaX Machines 90
2.3 CODES 92
ASCII Code 93
EBCDIC Code 94
Baudot,Morse,and BCD Codes 97
2.4 ANALOG AND DIGITAL SIGNALS 101
Digital Encoding Schemes 102
Analog Signals 105
Bit Rate 110
2.5 MODULATION AND DEMODULATION 115
Digital-to-Analog Conversion 116
Analog-to-Digital Conversion 121
2.6 MODEMS AND MODEM STANDARDS 124
Signal Constellation 126
Intelligent(Hayes Compatible)Modems 130
Cable Modems 131
NulI Modems 135
2.7 SUMMARY 135
REVIEW QUESTIONS 137
EXERCISES 139
REFERENCES 143
CHAPTER 3 DATA COMMUNICATION 145
Serial and Parallel Transmission 146
3.1 TRANSMISSION MODES 146
Asynchronous and Synchronous Transmission 147
Simplex,Half-Duplex,and Full-Duplex Communications 150
3.2 INTERFACE STANDARDS 151
RS-232 Interface 152
RS-232 Subsets 155
Null Modems 156
RS-449 Interface 157
X.21 Interface 159
3.3 MULTIPLEXING 161
Frequency-Division Multiplexing 163
Time-Division Multiplexing 165
Statistical Multiplexers 167
T-l Carrier 169
3.4 CONTENTION PROTOCOLS 172
Aloha Protocols 174
Carrier Sense Multiple Access 177
Collision Detection 180
Token Passing 183
Summary of Protocols 187
3.5 DATA COMPRESSION 188
Huffman Code 189
Run-Length Encoding 192
Relative Encoding 194
Lempel-Ziv Encoding 195
Image Compression 201
JPEG 203
MPEG 211
Summary of Compression Techniques 216
3.6 SUMMARY 217
REVIEW QUESTIONS 218
EXERCISES 220
REFERENCES 224
CHAPTER 4 DATA SECURITY AND INTEGRITY 226
4.1 I NTRODUCTION 226
Parity Checking Analysis 228
4.2 PARITY CHECKING 228
Double-Bit Error Detection 229
Burst Error Detection 229
4.3 CYCLIC REDUNDANCY CHECKS 231
Polynomial Division 232
How CRC Works 233
Analysis of CRC 235
CRC Implementation Using Circular Shifts 239
Single-Bit Error Correction 241
4.4 HAMMING CODES 241
Multiple-Bit Error Correction 244
Comparison of Error Detection and Error Correction 244
4.5 ENCRYPTION AND DECRYPTION 245
Caesar Cipher 247
Polyalphabetic Cipher 248
Transposition Cipher 250
Bit-Level Ciphering 251
Data Encryption Standard 252
Clipper Chip 256
Key Distribution and Protection 260
Merkle's Puzzles 260
Shamir's Method 261
4.6 PUBLIC KEY ENCRYPTION 262
RSA Algorithm 264
Digital Signatures 266
Authentication Using Hash-Based Schemes 268
Encryption Potpourri 272
Summary of Encryption Methods 272
4.7 VIRUSES,WORMS,AND HACKERS 275
Infecting Files 275
Memory-Resident Viruses 276
Virus Evolution 277
Virus Sources 281
The Internet Worm 281
Computer Hackers 283
4.8 SUMMARY 284
REVIEW QUESTIONS 286
EXERCISES 288
REFERENCES 291
CHAPTER 5 PROTOCOLCONCEPTS 293
5.1 INTRODUCTION 293
5.2 BASIC FLOW CONTROL 295
Signaling 295
Frame-Oriented Control 297
Protocol Efficiency 301
5.3 SLIDING WINDOW PROTOCOLS 304
Frame Format 306
Go-back-n Protocol 307
Selective Repeat Protocol 314
Sliding Window Protocol Efficiency 322
Summary of Protocols 324
5.4 PROTOCOL CORRECTNESS 325
Finite State Machines 325
Petri Nets 331
5.5 DATA LINK CONTROL PROTOCOLS 336
High-Level Data Link Control(HDLC) 336
Other Bit-Oriented Protocols 344
Binary Synchronous Communications Protocol 345
Summary:Data Link Protocols 349
5.6 CASE STUDY:KERMIT 350
Frame Format 351
Protocol 352
Commands 354
5.7 SUMMARY 356
REVIEW QUESTIONS 357
EXERCISES 359
REFERENCES 363
CHAPTER 6 LOCAL AREA N ETWORKING 364
6.1 NETWORK TOPOLOGIES 364
6.2 ETHERNET:IEEE STANDARD 802.3 367
Ethernet Components 368
Relation to OSI 368
Cable Specifications 371
Connecting Segments 373
Frame Format 374
Efficiency 375
6.3 TOKEN RING:IEEE STANDARD 802.5 379
Token and Frame Formats 381
Reserving and Claiming Tokens 383
Ring Maintenance 389
Efficiency 391
Other Ring Networks 392
6.4 TOKEN Bus:IEEE STANDARD 802.4 397
Token Bus Operations 399
Lost Tokens 402
Ring Initialization 403
Prioritizing Frames 404
6.5 INTERCONNECTING LANS 407
Layer 1 Connections 409
Layer 2 Connections 410
Bridging Different Types of LANs 411
Bridge Routing 413
Summary 426
6.6 CASE STUDY:NOVELL NETWARE 427
NetWare Configuration 427
Running Novell NetWare 429
Security and Integrity 431
Selected Novell Commands 434
Login Scripts 436
6.7 SUMMARY 439
REVIEW QUESTIONS 440
EXERCISES 443
REFERENCES 446
CHAPTER 7 WIDE AREA NETWORKING 448
7.1 INTRODUCTION 448
7.2 NETWORK ROUTING 451
Routing Tables 452
Types of Routing 453
Dijkstra's Algorithm 456
Bellman-Ford Algorithm 459
Link State Routing 466
Hierarchical Routing 467
Routing Information Protocol 470
Open Shortest Path First 471
？order Gateway Protocol 472
Congestion and Deadlock 473
Summary of Routing Techniques 473
7.3 PUBLIC DATA NETWORKS:THE X SERIES PROTOCOLS 478
Packet-Switched Network Modes 479
X.25 Public Data Network Interface Standard 481
Triple-X Standard for Non-X.25 Devices 486
7.4 INTERNET PROTOCOLS 490
Overview of TCP/IP 491
Internet Addressing 493
Domain Name System 495
IP Packets 497
Fragmentation 500
IP Routing 501
Intemet Control Message Protocol 504
IPv6 506
7.5 TRANSPORT PROTOCOLS 515
Transmission Control Protocol 518
OSI Transport Protocols 529
User Datagram Protocol 529
7.6 SOCKET PROGRAMMING 531
Sockets 532
Client/Server Model 532
Socket Data Structures 533
Socket Commands 535
Client/Server Example 535
7.7 SUMMARY 548
REVIEW QUESTIONS 551
EXERCISES 553
REFERENCES 557
CHAPTER 8 ADDITIONAL NETWORK PROTOCOLS 559
8.1 INTERNET APPLICATIONS 559
Virtual Terminal 559
Telnet 560
File Transfers 564
Simple Mail Transfer Protocol 571
Simple Network Management Protocol 573
8.2 WORLD WIDE WEB 576
Web Page Access 577
Hypertext Markup Language 579
HTML Forms 582
JavaScript and Client-side Programming 587
Common Gateway Interface and Server-side Programming 592
8.3 ELECTRONIC MAIL:X.400 AND X.500 STANDARDS 597
X.400 Mail Standards 598
X.500 Directory Service 606
8.4 INTEGRATED SERVICES DIGITAL NETWORK 610
Summary 610
ISDN Services 612
ISDN Architecture 613
Protocols 615
Broadband ISDN 624
8.5 ASYNCHRONOUS TRANSFER MODE 625
Benefits of Small Fixed-Size Cells 626
Overview of ATM Network 628
Switching 629
Reference Model 631
Cell Definition 633
Virtual Circuits and Paths 636
Connection Management 637
Adaptation Layers 639
8.6 SYSTEMS NETWORK ARCHITECTURE 646
Lower Layers Physical Link Control 647
Path Control 648
Transmission Conteol 654
Data Flow Control 657
Higher Layers 659
REVIEW QUESTIONS 661
EXERCISES 663
REFERENCES 665
GLOSSARY 667
ACRONYMS 695
INDEX 699