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Understanding Data Communications: From Fundamentals to Networking, 3rd Edition (Hardcover) 
by Gilbert Held (Author) "The main objective of this chapter is to obtain an appreciation of the use of communications to enhance our daily work and recreation..." (more)  
Key Phrases: United States, Gigabit Ethernet, Fast Ethernet (more...)  
4.0 out of 5 stars  
See all reviews (1 customer review) 
Editorial Reviews 
Review 
"...designed to provide a solid foundation on how data communications systems operate, why, where, and when certain types of equipment should be networked together, and the role of evolving communications technology." (SciTech Book News, Vol. 25, No. 4, December 2001) 
 
.,."designed to provide a solid foundation on how data communications systems operate, why, where, and when certain types of equipment should be networked together, and the role of evolving communications technology." (SciTech Book News, Vol. 25, No. 4, December 2001) 
CONTENTS 
Preface xix 
Acknowledgements xxi 
1 Communications in a Modern Society 1 
1.1 Applications 1 
1.1.1 Data collection 2 
1.1.2 Transaction processing 3 
1.1.3 Conversational time sharing 5 
1.1.4 Remote job entry 7 
1.1.5 Message switching 7 
1.1.6 Value-added carriers and electronic mail 8 
1.1.7 Office automation 12 
1.1.8 Electronic commerce 14 
1.1.9 Satellite transmission 16 
1.2 Constraints 16 
1.2.1 Throughput 17 
1.2.2 Response time 18 
1.2.3 Bandwidth 18 
1.2.4 Economics 19 
1.3 Emerging Trends 19 
1.4 ReviewQuestion s 20 
2 Basic Telegraph and Telephone Operations 23 
2.1 Evolution of Communications 23 
2.2 Telegraphy 24 
2.2.1 Operation 24 
2.2.2 Morse code 26 
2.2.3 Morse code limitations 27 
2.2.4 Start–stop signaling and the Baudot code 28 
2.2.5 Bits and codes 29 
2.3 Telephony 32 
2.3.1 Principle of operation 32 
2.3.2 Sound wave conversion 34 
2.3.3 The basic telephone connection 36 
2.3.4 Switchboards and central offices 37 
2.3.5 Numbering plans 39 
2.3.6 Geographic calling areas and network routing 40 
2.3.7 The world numbering plan 43 
2.4 ReviewQuestion s 43 
3Basic Circuit Parameters, Measurement Units and 
Media Overview 47 
3.1 Basic Circuit Parameters 47 
3.1.1 Frequency and bandwidth 47 
3.1.2 The telephone channel passband 49 
3.2 Measurement Units 50 
3.2.1 Power ratios 50 
3.2.2 Signal-to-noise ratio 52 
3.2.3 Reference points 54 
3.3 Media Overview56 
3.3.1 Twisted-pair cable 56 
3.3.2 Coaxial cable 61 
3.3.3 Microwave 63 
3.3.4 Fiber-optic transmission 64 
3.4 Channel Capacity 67 
3.4.1 Bit versus baud 67 
3.4.2 Nyquist relationship 67 
3.4.3 Shannon’s law68 
3.5 Structured Wiring 69 
3.5.1 The wiring closet 69 
3.5.2 The EIA/TIA-568 standard 69 
3.6 ReviewQue stions 72 
4 Fundamental Data Transmission Concepts 75 
4.1 Analog Line Connections 75 
4.1.1 The analog switched line 76 
4.1.2 Analog leased line 79 
4.1.3 Dedicated line 82 
4.1.4 Switched network vs leased line economics 83 
4.2 Types of Service and Transmission Devices 84 
4.2.1 Digital repeaters 85 
4.2.2 Modems 86 
4.2.3 Acoustic couplers 87 
4.2.4 Analog facilities 89 
4.2.5 Digital facilities 93 
4.2.6 Digital signaling 93 
4.2.7 Representative AT&T digital offerings 96 
4.3 Transmission Mode 98 
4.3.1 Simplex transmission 98 
4.3.2 Half-duplex transmission 99 
4.3.3 Full-duplex transmission 100 
4.3.4 Terminal and mainframe computer operating modes 101 
4.4 Transmission Techniques 103 
4.4.1 Asynchronous transmission 103 
4.4.2 Synchronous transmission 105 
4.5 Types of Transmission 106 
4.6 Wide Area Network Transmission Structures 107 
4.6.1 Mainframe computer-based network structure 108 
4.6.2 LAN network structure 109 
4.6.3 LAN internetworking structure 110 
4.7 Line Discipline 111 
4.8 Transmission Rate 113 
4.8.1 Analog service 113 
4.8.2 Digital service 114 
vi CONTENTS 
4.9 Transmission Codes 115 
4.9.1 Morse code 115 
4.9.2 Baudot code 116 
4.9.3 BCD code 116 
4.9.4 Extended binary-coded decimal interchange code (EBCDIC) 116 
4.9.5 ASCII code 118 
4.10 ReviewQue stions 122 
5 Terminals, Workstations and WAN and LAN 
Networking Overview 125 
5.1 Terminals 126 
5.1.1 Interactive terminal classification 126 
5.1.2 Terminal evolution 127 
5.2 Workstations and Other LAN Components 141 
5.2.1 Network interface card 141 
5.2.2 Hubs 142 
5.2.3 File server 143 
5.2.4 Print server 145 
5.2.5 Other types of servers 146 
5.3 Wide Area Networking Overview 146 
5.3.1 Multiplexing and data concentration 146 
5.3.2 Front-end processor 151 
5.3.3 Network configurations 151 
5.4 Local Area Networking Overview 152 
5.4.1 Repeaters 153 
5.4.2 Bridges 153 
5.4.3 Routers 154 
5.4.4 Gateways 155 
5.5 ReviewQuestion s 157 
6 Representative Standards Organizations: 
the OSI Reference Model 159 
6.1 National Standards Organizations 160 
6.1.1 American National Standards Institute (ANSI) 160 
6.1.2 Electronic Industries Association (EIA) 161 
6.1.3 Federal Information Processing Standards (FIPS) 163 
6.1.4 Institute of Electrical and Electronic Engineers (IEEE) 163 
6.1.5 British Standards Institution (BSI) 164 
6.1.6 Canadian Standards Association (CSA) 164 
6.2 International Standards Organizations 164 
6.2.1 International Telecommunications Union (ITU) 164 
6.2.2 International Standards Organization (ISO) 165 
6.3 De facto Standards 167 
6.3.1 AT&T compatibility 168 
6.3.2 Cross-licensed technology 169 
6.3.3 Bellcore/Telcordia Technology 169 
6.3.4 Internet standards 170 
6.4 The OSI Reference Model 171 
6.4.1 Layered architecture 172 
6.4.2 OSI layers 173 
6.4.3 Data flow176 
6.5 IEEE 802 Standards 177 
6.5.1 802 committees 177 
6.5.2 Data link subdivision 179 
6.6 ReviewQuestion s 180 
CONTENTS vii 
7 The Physical Layer, Cables, Connectors, Plugs 
and Jacks 183 
7.1 DTE/DCE Interfaces 184 
7.1.1 Connector overview186 
7.1.2 RS-232-C/D 188 
7.1.3 Differential signaling 198 
7.1.4 RS-449 200 
7.1.5 V.35 202 
7.1.6 RS-366-A 203 
7.1.7 X.21 and X.20 204 
7.1.8 X.21 bis 207 
7.1.9 RS-530 207 
7.1.10 High Speed Serial Interface 298 
7.1.11 High Performance Parallel Interface 214 
7.1.12 Universal Serial Bus 216 
7.1.13 IEEE 1394 (FireWire) 218 
7.2 Cables and Connectors 222 
7.2.1 Twisted-pair cable 222 
7.2.2 Low-capacitance shielded cable 223 
7.2.3 Ribbon cable 223 
7.2.4 The RS-232 null modem 223 
7.2.5 RS-232 cabling tricks 225 
7.3 Plugs and Jacks 226 
7.3.1 Connecting arrangements 228 
7.3.2 Telephone options 230 
7.3.3 Ordering the business line 231 
7.3.4 LAN connectivity 232 
7.4 ReviewQue stions 233 
8 Basic Transmission Devices: Line Drivers, 
Modems, and Service Units 235 
8.1 Line Drivers 236 
8.1.1 Direct connection 236 
8.1.2 Using line drivers 239 
8.2 Modem Operations 243 
8.2.1 The modulation process 243 
8.2.2 Bps vs. baud 246 
8.2.3 Voice circuit parameters 246 
8.2.4 Combined modulation techniques 247 
8.2.5 Mode of transmission 253 
8.2.6 Transmission techniques 254 
8.2.7 Modem classification 255 
8.2.8 Limited-distance modems 256 
8.2.9 Line-type operations 257 
8.2.10 Reverse and secondary channels 257 
8.2.11 Equalization 258 
8.2.12 Synchronization 260 
8.2.13 Multiport capability 260 
8.2.14 Security capability 261 
8.2.15 Multiple speed selection capability 261 
8.2.16 Voice/data capability 262 
8.2.17 Modem handshaking 262 
8.2.18 Self-testing features 263 
8.2.19 Modem indicators 265 
8.2.20 Modern operations and compatibility 265 
viii CONTENTS 
8.3 Intelligent Modems 289 
8.3.1 Hayes command set modems 289 
8.3.2 Key intelligent modem features 296 
8.3.3 Microcom Networking Protocol (MNP) 302 
8.3.4 Data compression 306 
8.3.5 MNP Class 5 compression 306 
8.3.6 MNP Class 7 enhanced data compression 308 
8.3.7 V.42bis 311 
8.4 Broadband Modems 312 
8.4.1 Telephone and cable TV infrastructure 313 
8.4.2 Cable modems 317 
8.4.3 DSL modems 324 
8.5 Service Units 330 
8.5.1 The DSU 331 
8.5.2 The CSU 331 
8.6 ReviewQuestion s 332 
9 Regulators and Carriers 335 
9.1 Regulators 336 
9.1.1 US regulatory evolution 336 
9.1.2 International regulatory authorities 342 
9.2 Carrier Offerings 343 
9.2.1 AT&T system evolution 343 
9.2.2 The Bell system 345 
9.2.3 The regional Bell operating companies 346 
9.2.4 AT&T service offerings 349 
9.2.5 Regional Bell operating company offerings 355 
9.3 ATM Overview356 
9.4 ReviewQuestion s 357 
10 Transmission Errors: Causes, Measurements and 
Correction Methods 359 
10.1 Causes of Transmission Errors 359 
10.2 Performance Measurements 360 
10.2.1 Bit error rate 360 
10.2.2 Bit error rate tester 360 
10.2.3 BERT time 362 
10.2.4 Performance classifications 362 
10.2.5 Block error rate testing 364 
10.2.6 Error-free second testing 365 
10.3 Error Detection and Correction Techniques 365 
10.3.1 Asynchronous transmission 365 
10.3.2 Synchronous transmission 370 
10.4 ReviewQue stions 374 
11 The WAN Data Link Layer 377 
11.1 Terminal and Data Link Protocols: Characteristics 
and Functions 378 
11.1.1 Transmission sequence 379 
11.1.2 Error control 379 
11.2 Types of Protocol 380 
11.2.1 Teletypewriter protocols 380 
11.2.2 PC file transfer protocols 385 
CONTENTS ix 
11.2.3 Bisynchronous protocols 395 
11.2.4. Digital Data Communications Message Protocol (DDCMP) 400 
11.2.5 Bit-oriented line control procedures 402 
11.3 ReviewQuestio ns 407 
12 Increasing WAN Line Utilization 409 
12.1 Multiplexers 410 
12.1.1 Evolution 410 
12.1.2 Device support 410 
12.1.3 Multiplexing techniques 411 
12.2 Control Units 439 
12.2.1 Control unit concept 440 
12.2.2 Attachment methods 440 
12.2.3 Unit operation 442 
12.2.4 Breaking the closed system 443 
12.3 ReviewQuestio ns 445 
13Local Area Networks 449 
13.1 Origin 449 
13.2 Comparison with WANs 450 
13.2.1 Geographical area 450 
13.2.2 Data transmission and error rates 450 
13.2.3 Ownership 451 
13.2.4 Regulation 451 
13.2.5 Data routing and topology 451 
13.2.6 Type of information carried 452 
13.3 Utilization Benefits 452 
13.3.1 Peripheral sharing 453 
13.3.2 Common software access 453 
13.3.3 Electronic mail 453 
13.3.4 Gateway access to mainframes 453 
13.3.5 Internet access 453 
13.3.6 Virtual private network operations 454 
13.4 Technological Characteristics 454 
13.4.1 Topology 454 
13.4.2 Comparison of topologies 456 
13.4.3 Signaling methods 457 
13.4.4 Transmission medium 460 
13.4.5 Access methods 460 
13.5 Ethernet Networks 465 
13.5.1 Original network components 465 
13.5.2 IEEE 802.3 networks 468 
13.5.3 Frame composition 490 
13.5.4 Media access control overview495 
13.5.5 Logical link control overview495 
13.5.6 Other Ethernet frame types 498 
13.6 Token-Ring 504 
13.6.1 Topology 504 
13.6.2 Redundant versus non-redundant main ring paths 506 
13.6.3 Cabling and device restrictions 507 
13.6.4 Constraints 510 
13.6.5 High speed Token-Ring 514 
13.6.6 Transmission formats 515 
13.6.7 Medium access control 524 
13.6.8 Logical link control 527 
13.7 ReviewQuestio ns 528 
x CONTENTS 
14 Basic LAN Internetworking 531 
14.1 Bridge Operations 531 
14.1.1 Types of bridge 531 
14.1.2 Network utilization 544 
14.2 The Switching Hub 546 
14.2.1 Basic components 546 
14.2.2 Delay times 547 
14.2.3 Key advantages of use 549 
14.2.4 Switching techniques 549 
14.2.5 Port address support 553 
14.2.6 Switching architecture 556 
14.2.7 High-speed port operations 557 
14.2.8 Summary 558 
14.3 Router Operations 558 
14.3.1 Basic operation and use of routing tables 559 
14.3.2 Networking capability 560 
14.3.3 Communication, transport and routing protocols 561 
14.3.4 Router classifications 563 
14.3.5 Routing protocols 566 
14.4 ReviewQue stions 575 
15 Digital Transmission Systems and 
Equipment 577 
15.1 The T and E Carriers 578 
15.1.1 Channel banks 578 
15.2 T1 Multiplexers 596 
15.2.1 Waveform-based voice digitization modules 597 
15.2.2 Vocoding 598 
15.2.3 Hybrid coding 601 
15.2.4 T1 multiplexer employment 602 
15.3 The T3 Carrier 605 
15.3.1 T3 circuit types 606 
15.3.2 Evolution 606 
15.3.3 T3 framing 609 
15.4 DDS, ASDS and KiloStream facilities 615 
15.4.1 Applications 616 
15.4.2 ASDS 616 
15.4.3 KiloStream service 617 
15.5 Integrated Services Digital Network (ISDN) 619 
15.5.1 Concept behind ISDN 619 
15.5.2 ISDN architecture 620 
15.5.3 Network characteristics 621 
15.5.4 ISDN layers 625 
15.6 ReviewQue stions 628 
16 Network Architecture 631 
16.1 SNA Overview632 
16.1.1 SNA elements 634 
16.1.2 System Service Control Point (SSCP) 634 
16.1.3 Network nodes 634 
16.1.4 The physical unit 635 
16.1.5 The logical unit 635 
16.1.6 SNA network structure 635 
16.1.7 Types of physical unit 637 
CONTENTS xi 
16.1.8 Multiple domains 637 
16.1.9 SNA layers 639 
16.1.10 SNA developments 641 
16.1.11 SNA sessions 641 
16.2 Advanced Peer-to-Peer Networking (APPN) 644 
16.2.1 APPC concepts 644 
16.2.2 APPN architecture 645 
16.2.3 Operation 646 
16.3 TCP/IP 649 
16.3.1 The rise of the Internet 650 
16.3.2 The TCP/IP protocol suite 651 
16.3.3 Applications 653 
16.3.4 TCP/IP communications 663 
16.3.5 The Internet Protocol (IP) 664 
16.3.6 Domain Name Service 679 
16.4 Internetworking 681 
16.4.1 SNA gateway operations 682 
16.4.2 Supporting multiple protocols 690 
16.4.3 Data Link Switching 693 
16.5 ReviewQuestio ns 694 
17 Packet Networks 697 
17.1 Packet Switching Overview 698 
17.2 X.25 Networks 700 
17.2.1 Development period 700 
17.2.2 Need for PADs 700 
17.2.3 X.25 layers 705 
17.2.4 Methods of connection 708 
17.2.5 Utilization costs 709 
17.2.6 Tymnet 711 
17.2.7 Network information 713 
17.2.8 Features 713 
17.2.9 Protocol conversion 715 
17.2.10 LAN interconnectivity 716 
17.3 Frame Relay 717 
17.3.1 Comparison to X.25 717 
17.3.2 Standards 719 
17.3.3 Network access 720 
17.3.4 Frame construction 721 
17.3.5 Service parameters 729 
17.3.6 FRAD features 734 
17.3.7 Voice over Frame Relay 740 
17.4 ReviewQuestio ns 745 
18 Communications Software 749 
18.1 Terminal Emulation Software Features 749 
18.1.1 Hardware utilization 752 
18.1.2 Software utilization 753 
18.1.3 Operational consideration 754 
18.1.4 Documentation 757 
18.1.5 Dialing 757 
18.1.6 Transmission 762 
18.1.7 Performance efficiency 766 
18.1.8 Performance flexibility 770 
18.1.9 Security performance 772 
xii CONTENTS 
18.2 Terminal Emulation Program Examination 774 
18.2.1 Procomm Plus for Windows 775 
18.2.2 HyperTerminal 777 
18.2.3 IBM PC/3270 780 
18.3 Web Browsers 783 
18.3.1 Microsoft Internet Explorer 784 
18.3.2 LAN operation 788 
18.4 ReviewQue stions 789 
19 Fiber-Optic, Satellite and Wireless Terrestrial 
Communications 791 
19.1 Fiber-Optic Transmission Systems 792 
19.1.1 System components 792 
19.1.2 Transmission advantages 799 
19.1.3 Limitations of use 801 
19.1.4 Utilization economics 802 
19.1.5 Carrier utilization 805 
19.1.6 SONET 806 
19.2 Satellite Communications Systems 810 
19.2.1 Operation overview810 
19.2.2 Satellite access 810 
19.2.3 Very small aperture terminal (VSAT) 812 
19.2.4 Lowearth orbit satellites 812 
19.3 Wireless Terrestrial Communications 814 
19.3.1 Cellular communications 814 
19.3.2 Wireless LANs 820 
19.4 ReviewQue stions 821 
20 Evolving Technologies 823 
20.1 ATM 823 
20.1.1 Cell size 823 
20.1.2 Scalability 824 
20.1.3 Transparency 825 
20.1.4 Traffic classification 825 
20.2 The ATM Protocol Stack 825 
20.2.1 ATM Adaptation Layer 825 
20.2.2 The ATM Layer 826 
20.2.3 Physical Layer 827 
20.3 ATM Operation 827 
20.3.1 Components 827 
20.3.2 Network Interfaces 829 
20.3.3 The ATM cell header 830 
20.3.4 ATM connections and cell switching 833 
20.4 Virtual Private Networking 835 
20.4.1 Rationale for use 836 
20.4.2 Reliability 837 
20.4.3 Problem areas 837 
20.5 ReviewQue stions 838 
Index 841 |   
 
 
 
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