L

Computer Networks And Internets

With Internet Applications

THIRD EDITION

DOUGLAS E. COMER

Department of Computer Sciences Purdue University

West Lafayette, IN 47907

PRENTICE HAll Upper Saddle River, New Jersey 07458

Contents

Preface xxv

Chapter 1 Introduction 1

1.1 Growth Of Computer Networking 1 1.2 Complexity In Network Systems 2 1.3 Mastering The Complexity 2 1.4 Concepts And Terminology 3 1.5 Organization Of The Text 3 1.6 Summary 4

Chapter 2 Motivation And Tools 7

2.1 Introduction 7 2.2 Resource Sharing 7 2.3 Growth Of The Internet 8 2.4 Probing The Internet 11 2.5 Interpreting A Ping Response 12 2.6 Tracing A Route 14 2.7 Summary 15

Chapter 3 Network Programming And Applications 17

3.1 Introduction 17 3.2 Network Communication 18 3.3 Client-Server ComputinR 18

viii Contents

PART I Data Transmission

Chapter 4 Transmission Media

4.1 Introduction 45 4.2 Copper Wires 45 4.3 Glass Fibers 47 4.4 Radio 48 4.5 Satellites 48 4.6 Geosynchronous Satellites 49 4.7 Low Earth Orbit Satellites 50 4.8 Low Earth Orbit Satellite Arrays 50 4.9 Microwave 51 4.10 Infrared 51 4.11 Light From A Laser 52 4.12 Summary 52

Chapter 5 Local Asynchronous Communication (RS-232)

5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 5.10 5.11

Introduction 55 The Need For Asynchronous Communication 56 Using Electric Current To Send Bits 56 Standards For Communication 57 Baud Rate, Framing, And Errors 59 Full Duplex Asynchronous Communication 60 Limitations Of Real Hardware 61 Hardware Bandwidth And The Transmission Of Bits The Effect Of Noise On Communication 62 Significance For Data Networking 63 Summary 64

62

45

55

Chapter 6 Long-Distance Communication (Carriers, Modulation, And 67 Modems)

6.1 Introduction 67 6.2 Sending Signals Across Long Distances 67 6.3 Modem Hardware Used For Modulation And Demodulation 70 6.4 Leased Analog Data Circuits 71 6.5 Optical, Radio Frequency, And Dialup Modems 72 6.6 Carrier Frequencies And MUltiplexing 73

'I

Contents

6.7 Baseband And Broadband Technologies 75 6.8 Wave Division Multiplexing 75 6.9 Spread Spectrum 76 6.10 Time Division MUltiplexing 76 6.11 Summary 77

PART 11 Packet Transmission

Chapter 7 Packets, Frames, And Error Detection

7.1 Introduction 81 7.2 The Concept Of Packets 81 7.3 Packets And Time-Division Multiplexing 83 7.4 Packets And Hardware Frames 84 7.5 Byte Stuffing 85 7.6 Transmission Errors 87 7.7 Parity Bits And Parity Checking 87 7.8 Probability, Mathematics, And Error Detection 88 7.9 Detecting Errors With Checksums 89 7.10 Detecting Errors With Cyclic Redundancy Checks 90 7.11 Combining Building Blocks 92 7.12 Burst Errors 93 7.13 Frame Format And Error Detection Mechanisms 93 7.14 Summary 94

Chapter 8 LAN Technologies And Network Topology

8.1 Introduction 99 8.2 Direct Point-to-Point Communication 100 8.3 Shared Communication Channels 102 8.4 Significance Of LANs And Locality Of Reference 102 8.5 LAN Topologies 103 8.6 Example Bus Network: Ethernet 106 8.7 Carrier Sense On Multi-Access Networks (CSMA) 108 8.8 Collision Detection And Backoff With CSMAlCD 108 8.9 802.11 Wireless LANs And CSMAlCA 110 8.10 Another Example Bus Network: LocalTalk 111 8.11 Example Ring Network: IBM Token Ring 112 8.12 Another Example Ring Network: FDDI 114 8.13 Example Star Network: ATM 115 8.14 Summary 117

ix

81

99

x

Chapter 9 Hardware Addressing And Frame Type Identification

9.1 Introduction 121 9.2 Specifying A Recipient 122 9.3 How LAN Hardware Uses Addresses To Filter Packets 122 9.4 Fonnat Of A Physical Address 124 9.5 Broadcasting 125 9.6 Multicasting 126 9.7 Multicast Addressing 127 9.8 Identifying Packet Contents 128 9.9 Frame Headers And Frame Fonnat 128 9.10 An Example Frame Fonnat 129 9.11 Using Networks That Do Not Have Self-Identifying Frames 131 9.12 Network Analyzers, Physical Addresses, Frame Types 133 9.13 Summary 134 9.14 Ethemet Address Assignment 136

Contents

121

Chapter 10 LAN Wiring, Physical Topology, And Interface Hardware 139

10.1 Introduction 139 10.2 Speeds Of LANs And Computers 139 10.3 Network Inteiface Hardware 140 10.4 The Connection Between A NIC And A Network 142 10.5 Original Thick Ethemet Wiring 142 10.6 Connection Multiplexing 144 10.7 Thin Ethemet Wiring 145 10.8 Twisted Pair Ethemet 146 10.9 Advantages And Disadvantages Of Wiring Schemes 148 10.10 The Topology Paradox 150 10.11 Network Inteiface Cards And Wiring Schemes 150 10.12 Wiring Schemes And Other Network Technologies 152 10.13 Summary 153

Chapter 11 Extending LANs: Fiber Modems, Repeaters, Bridges, and 155 Switches

11.1 11.2 11.3 11.4 11.5 11.6

Introduction 155 Distance Limitation And LAN Design Fiber Optic Extensions 156 Repeaters 157 Bridges 160 Frame Filtering 161

155

Contents xi

11.7 Startup And Steady State Behavior Of Bridged Nef'vvorks 162 11.8 Planning A Bridged Nef'vvork 162 11.9 Bridging Bef'vveen Buildings 163 11.10 Bridging Across Longer Distances 164 11.11 A Cycle Of Bridges 166 11.12 Distributed Spanning Tree 167 11.13 Switching 168 11.14 Combining Switches And Hubs 169 11.15 Bridging And Switching With Other Technologies 169 11.16 Summary 170

Chapter 12 Long-Distance Digital Connection Technologies

12.1 Introduction 173 12.2 Digital Telephony 173 12.3 Synchronous Communication 175 12.4 Digital Circuits And DSu/CSUs 176 12.5 Telephone Standards 177 12.6 DS Terminology And Data Rates 178 12.7 Lower Capacity Circuits 179 12.8 Intermediate Capacity Digital Circuits 179 12.9 Highest Capacity Circuits 180 12.10 Optical Carrier Standards 181 12.11 The C Suffix 181 12.12 Synchronous Optical NETwork (SON ET) 181 12.13 The Local Subscriber Loop 183 12.14 ISDN 183 12.15 Asymmetric Digital Subscriber Line Technology 184 12.16 Other DSL Technologies 187 12.17 Cable Modem Technology 188 12.18 Upstream Communication 189 12.19 Hybrid Fiber Coax 190 12.20 Fiber To The Curb 191 12.21 Alternatives For Special Cases 191 12.22 Broadcast Satellite Systems 192 12.23 Summary 193

173

Chapter 13 WAN Technologies And Routing 197

13.1 Introduction 197 13.2 Large Nef'vvorks And Wide Areas 197 13.3 Packet Switches 198

xii Contents

13.4 Forming A WAN 199 13.S Store And Forward 200 13.6 Physical Addressing In A WAN 201 13.7 Next-Hop Forwarding 201 13.8 Source Independence 203 13.9 Relationship Of Hierarchical Addresses To Routing 203 13.10 Routing InA WAN 204 13.11 Use Of Default Routes 206 13.12 Routing Table Computation 207 13.13 Shortest Path Computation In A Graph 207 13.14 Distributed Route Computation 209 13.1S Distance Vector Routing 209 13.16 Link-State Routing (SPF) 212 13.17 Example WAN Technologies 212 13.18 Summary 214

Chapter 14 Connection-Oriented Networking And ATM

14.1 Introduction 217 14.2 A Single, Global Network 217 14.3 ISDN And ATM 218 14.4 ATM Design And Cells 218 14.S Connection-Oriented Service 220 14.6 VPIIVCI 220 14.7 Labels And Label Switching 221 14.8 An Example Trip Through An ATM Network 222 14.9 Permanent Virtual Circuits 223 14.10 Switched Virtual Circuits 224 14.11 Quality Of Service 225 14.12 The Motivation For Cells And Label Switching 225 14.13 ATM Data Transmission And AALS 226 14.14 Critique Of ATM 227 14.1S Summary 228

217

Chapter 15 Network Characteristics: Ownership, Service Paradigm, 231 And Performance

lS.l Introduction 231 lS.2 Network Ownership 232 lS.3 Privacy And Public Networks 233 lS.4 Advantages And Disadvantages 233 lS.5 Virtual Private Networks 234

Contents

15.6 Guaranteeing Absolute Privacy 235 15.7 Service Paradigm 235 15.8 Connection-Oriented Service Paradigm 236 15.9 Connection less Service Paradigm 237 15.10 Interior And Exterior Service Paradigms 237 15.11 Comparison Of Service Paradigms 238 15.12 Examples Of Service Paradigms 238 15.13 Addresses And Connection Identifiers 239 15.14 Network Peiformance Characteristics 240 15.15 litter 244 15.16 Summary 244

Chapter 16 Protocols And Layering

16.1 Introduction 247 16.2 The Need For Protocols 247 16.3 Protocol Suites 248 16.4 A Plan For Protocol Design 249 16.5 The Seven Layers 249 16.6 Stacks: Layered Software 251 16.7 How Layered Software Works 253 16.8 Multiple, Nested Headers 254 16.9 The Scientific Basis For Layering 254 16.10 Techniques Protocols Use 255 16.11 The Art Of Protocol Design 264 16.12 Summary 264

PART III Internetworking

xiii

247

Chapter 17 Internetworking: Concepts, Architecture, and Protocols 269

17.1 Introduction 269 17.2 The Motivation For Internetworking 269 17.3 The Concept Of Universal Service 270 17.4 Universal Service In A Heterogeneous World 270 17.5 Internetworking 271 17.6 Physical Network Connection With Routers 271 17.7 Internet Architecture 272 17.8 Achieving Universal Service 273 17.9 A Virtual Network 273 17.10 Protocols For Internetworking 275

xiv

17.11 Significance Of Internetworking And TCPIIP 275 17.12 Layering And TCPIIP Protocols 276 17.13 Host Computers, Routers, And Protocol Layers 277 17.14 Summary 278

Chapter 18 JP: Internet Protocol Addresses

18.1 Introduction 281 18.2 Addresses For The Virtual Internet 281 18.3 The IP Addressing Scheme 282 18.4 The IP Address Hierarchy 283 18.5 Original Classes Of IP Addresses 283 18.6 Computing The Class of An Address 285 18.7 Dotted Decimal Notation 286 18.8 Classes And Dotted Decimal Notation 287 18.9 Division Of The Address Space 287 18.10 Authority For Addresses 288 18.11 A Classful Addressing Example 288 18.12 Subnet And Classless Addressing 289 18.13 Address Masks 290 18.14 CIDR Notation 291 18.15 A CIDR Address Block Example 291 18.16 CIDR Host Addresses 292 18.17 Special IP Addresses 293 18.18 Summary Of Special IP Addresses 294 18.19 The Berkeley Broadcast Address Form 295 18.20 Routers And The IP Addressing Principle 295 18.21 Multi-Homed Hosts 297 18.22 Summary 297

Contents

281

Chapter 19 Binding Protocol Addresses (ARP) 301

19.1 Introduction 301 19.2 Protocol Addresses And Packet Delivery 302 19.3 Address Resolution 302 19.4 Address Resolution Techniques 303 19.5 Address Resolution With Table Lookup 304 19.6 Address Resolution With Closed-Form Computation 305 19.7 Address Resolution With Message Exchange 306 19.8 Address Resolution Protocol 307 19.9 ARP Message Delivery 308 19.10 ARP Message Format 309

Contents

19.11 Sending An ARP Message 310 19.12 Identifying ARP Frames 311 19.13 Caching ARP Responses 311 19.14 Processing An Incoming ARP Message 312 19.15 Layering, Address Resolution, Protocol Addresses 313 19.16 Summary 314

Chapter 20 IP Datagrams And Datagram Forwarding

20.1 Introduction 317 20.2 Connectionless Service 317 20.3 Virtual Packets 318 20.4 The IP Datagram 319 20.5 F01warding An IP Datagram 320 20.6 IP Addresses And Routing Table Entries 321 20.7 The Mask Field And Datagram Forwarding 322 20.8 Destination And Next-Hop Addresses 322 20.9 Best-Effort Delivery 323 20.10 The IP Datagram Header Format 324 20.11 Summary 325

xv

317

Chapter 21 IP Encapsulation, Fragmentation, And Reassembly 329

21.1 Introduction 329 21.2 Datagram Transmission And Frames 329 21.3 Encapsulation 330 21.4 Transmission Across An Internet 331 21.5 MTU, Datagram Size, And Encapsulation 332 21.6 Reassembly 334 21.7 Identifying A Datagram 334 21.8 Fragment Loss 335 21.9 Fragmenting A Fragment 335 21.10 Summary 336

Chapter 22 The Future IP (IPv6) 339

22.1 Introduction 339 22.2 The Success Of IP 339 22.3 The Motivation For Change 340 22.4 A Name And A Version Number 341 22.5 IPv6 Features 341

xvi

22.6 IPv6 Datagram Format 342 22.7 IPv6 Base Header Format 342 22.8 How IPv6 Handles Multiple Headers 344 22.9 Fragmentation, Reassembly, And Path MTU 345 22.10 The Purpose Of Multiple Headers 346 22.11 IPv6 Addressing 347 22.12 IPv6 Colon Hexadecimal Notation 348 22.13 Summary 349

Chapter 23 An Error Reporting Mechanism (ICMP)

23.1 Introduction 351 23.2 Best-Effort Semantics And Error Detection 351 23.3 Internet Control Message Protocol 352 23.4 ICMP Message Transport 355 23.5 Using ICMP Messages To Test Reachability 356 23.6 Using ICMP To Trace A Route 356 23.7 The Last Address Printed By Traceroute 357 23.8 Using ICMP For Path MTU Discovery 358 23.9 Summary 359

Chapter 24 TCP: Reliable Transport Service

24.1 24.2 24.3 24.4 24.5 24.6 24.7 24.8 24.9 24.10 24.11 24,12 24.13 24.14

Introduction 361 The Need For Reliable Transport 361 The Transmission Control Protocol 362 The Service TCP Provides To Applications End-To-End Service And Datagrams 363 Achieving Reliability 364 Packet Loss And Retransmission 365 Adaptive Retransmission 366 Comparison Of Re transmission .Times 367 Buffers, Flow Control, And Windows 367 Three-Way Handshake 369 Congestion Control 370 TCP Segment Format 370 Summary 371

362

Contents

351

361

............---r

Contents

Chapter 25 Internet Routing

25.1 Introduction 375 25.2 Static Vs. Dynamic Routing 375 25.3 Static Routing In Hosts And A Default Route 376 25.4 Dynamic Routing And Routers 377 25.5 Routing In The Global Internet 378 25.6 Autonomous System Concept 379 25.7 The Two Types Of Internet Routing Protocols 380 25.8 Routes And Data Traffic 382 25.9 The Border Gateway Protocol (BGP) 382 25.10 The Routing Information Protocol (RIP) 384 25.11 RIP Packet Format 385 25.12 The Open Shortest Path First Protocol (OSPF) 386 25.13 An Example OSPF Graph 387 25.14 OSPF Areas 388 25.15 Multicast Routing 388 25.16 Summary 392

PART IV Network Applications

Chapter 26 Client-Server Interaction

26.1 Introduction 397 26.2 The Functionality Application Software Provides 398 26.3 The Functionality An Internet Provides 398 26.4 Making Contact 399 26.5 The Client-Server Paradigm 399 26.6 Characteristics Of Clients And Servers 400 26.7 Server Programs And Server-Class Computers 400 26.8 Requests, Responses, And Direction Of Data Flow 401 26.9 Transport Protocols and Client-Server Interaction 401 26.10 Multiple Services On One Computer 402 26.11 Identifying A Particular Service 403 26.12 Multiple Copies Of A Server For A Single Service 403 26.13 Dynamic Server Creation 404 26.14 Transport Protocols And Unambiguous Communication 404 26.15 Connection-Or.iented And Connectionless Transport 405 26.16 A Service Reachable Through Multiple Protocols 406 26.17 Complex Client-Server Interactions 406 26.18 Interactions And Circular Dependencies 407 26.19 Summary 407 "

xvii

375

397

Contents

rhe Socket Interface 411

luction 411 ~ation Program Interface 411 ocket API 412 ts And Socket Libraries 412 t Communication And UNIX 110 413 ts, Descriptors, And Network 110 414 "teters And The Socket API 414 dures That Implement The Socket API 415 And Write With Sockets 421 Socket Procedures 421

ts, Threads, And Inheritance 422 ary 422

;xample Of A Client And A Server

'uction 425 ~ction-Oriented Communication 425 :ample Service 426 land-Line Arguments For The Example Programs 426 nce Of Socket Procedure Calls 426 For Example Client 428 For Example Server 431 n Service And Multiple Recv Calls 433 t Procedures And Blocking 434 if The Code And Error Reporting 434 The Example Client With Another Service 435 Another Client To Test The Server 435 ary 436

425

~aming With The Domain Name System 439

:uction 439 ure Of Computer Names 440 -aphic Structure 442 in Names Within An Organization 442 WS Client-Server Model 444 'NS Server Hierarchy 444 . Architectures 445 ~ty Of Reference And Multiple Servers 447 Among Servers 447

1

Contents xix

29.10 Resolving A Name 447 29.11 Optimization Of DNS Performance 449 29.12 Types Of DNS Entries 450 29.13 Aliases Using The CNAME Type 450 29.14 An Important Consequence Of Multiple Types 451 29.15 Abbreviations And The DNS 451 29.16 Summary 452

Chapter 30 Electronic Mail Representation And Transfer

30.1 Introduction 455 30.2 The Electronic Mail Paradigm 455 30.3 Electronic Mailboxes And Addresses 456 30.4 Electronic Mail Message Format 457 30.5 Carbon Copies 459 30.6 Multipurpose Internet Mail Extensions 459 30.7 E-mail And Application Programs 461 30.8 Mail Transfer 461 30.9 The Simple Mail Transfer Protocol 462 30.10 Optimizing For Multiple Recipients On A Computer 462 30.11 Mail Exploders, Lists, And Forwarders 462 30.12 Mail Gateways 463 30.13 Automated Mailing Lists 464 30.14 Mail Relays And E-mail Addresses 465 30.15 Mailbox Access 466 30.16 Dialup Connections And POP 468 30.17 Summary 468

455

Chapter 31 File Transfer And Remote File Access 471

31.1 31.2 31.3 31.4 31.5 31.6 31.7 31.8 31.9 31.10

Introduction 471 Data Transfer And Distributed Computation 471 Saving Intermediate Results 472 Generalized File Transfer 472 Interactive And Batch Transfer Paradigms 473 The File Transfer Protocol 474 FTP General Model And User Interface 474 FTP Commands 475 Connections, Authorization, And File Permissions Anonymous File Access 477

476

xx Contents

31.11 File Transfer In Either Direction 477 31.12 Wildcard Expansion In File Names 478 31.13 File Name Translation 478 31.14 Changing Directories And Listing Contents 478 31.15 File Types And Transfer Modes 479 31.16 Example Of Using FTP 480 31.17 Verbose Output 482 31.18 Client-Server Interaction In FTP 482 31.19 Control And Data Connections 483 31.20 Data Connections And End Of File 484 31.21 Trivial File Transfer Protocol 484 31.22 Network File System 485 31.23 Summary 486

Chapter 32 World Wide Web Pages And Browsing 489

32.1 Introduction 489 32.2 Browser Interface 489 32.3 Hypertext And Hypermedia 490 32.4 Document Representation 490 32.5 HTML Format And Representation 491 32.6 Example HTML Formatting Tags 493 32.7 Headings 493 32.8 Lists 494 32.9 Embedding Graphics Images In A Web Page 494 32.10 Identifying A Page 495 32.11 Hypertext Links From One Document To Another 496 32.12 Client-Server Interaction 497 32.13 Web Document Transfer And HTTP 498 32.14 Browser Architecture 499 32.15 Optional Clients 500 32.16 Caching In Web Browsers 501 32~17 HTTPSuppo'rtFdr Cachin:g----502 32.18 Alternative Transfer Protocols 503 32.19 Other Markup Languages 503 32.20 Summary 504

Chapter 33 Dynamic Web Document Technologies (CGI, ASP, JSP, 509 PHP, Cold Fusion)

33.1 Introduction 509 33.2 Three Basic Types of Web Documents 510

Contents xxi

33.3 Advantages And Disadvantages Of Each Document Type 510 33.4 Implementation Of Dynamic Documents 512 33.5 The CGI Standard 513 33.6 Output From A CGI Program 513 33.7 An Example CGI Program 514 33.8 Parameters And Environment Variables 516 33.9 State Information And Cookies 517 33.10 A CGI Script With Long-Term State Information 517 33.11 A CGI Script With Short-Term State Information 519 33.12 Forms And Interaction 522 33.13 Server-Side Scripting Technologies 523 33.14 Summary 524

Chapter 34 Technology For Active Web Documents (Java, 527 JavaScript)

34.1 Introduction 527 34.2 An Early Form Of Continuous Update 528 34.3 Active Documents And Server Overhead 529 34.4 Active Document Representation And Translation 529 34.5 Java Technology 531 34.6 The Java Programming Language 531 34.7 The Java Run-Time Environment 533 34.8 The Java Library 534 34.9 A Graphics Toolkit 535 34.10 Using Java Graphics On A Particular Computer 536 34.11 Java Interpreters And Browsers 537 34.12 Compiling A Java Program . 537 34.13 An Example Applet 538 34.14 Invoking An Applet 540 34.15 Example Of Interaction With A Browser 541 34.16 Errors And Exception Handling ·543 34.17 JavaScript Technology 543 34.18 Alternatives 545 34.19 Summary 546

Chapter 35 RPC and Middleware 549

35.1 Introduction 549 35.2 Programming Clients And Servers 549 35.3 Remote Procedure Call Paradigm 550 35.4 RPC Paradigm 552

xxii

35.5 35.6 35.7 35.8

Communication Stubs 554 External Data Representation 555 Middleware And Object-Oriented Middleware Summary 558

Chapter 36 Network Management (SNMP)

36.1 Introduction 561 36.2 Managing An Internet 561 36.3 The Danger Of Hidden Failures 562 36.4 Network Management Software 563 36.5 Clients, Servers, Managers, And Agents 563 36.6 Simple Network Management Protocol 564 36.7 Fetch-Store Paradigm 564 36.8 The MIB And Object Names 565 36.9 The Variety Of MIB Variables 566

556

36.10 MIB Variables That Correspond To Arrays 566 36.11 Summary 567

Chapter 37 Network Security

37.1 Introduction 569 37.2 Secure Networks And Policies 569 37.3 Aspects Of Security 570 37.4 Responsibility And Control 571 37.5 Integrity Mechanisms 571 37.6 Access Control And Passwords 572 37.7 Encryption And Confidentiality 572 37.8 Public Key Encryption 573 37.9 Authentication With Digital Signatures 573 37.10 Internet Firewall Concept 574 37.11 Packet Filtering 576 ... -.---. 37.12 Using Packet Filters To Create A Firewall 577 37.13 Virtual Private Networks 578 37.14 Tunneling 579 37.15 Summary 580

Chapter 38 Initialization (Configuration)

38.1 38.2

Introduction Bootstrapping

583 583

Contents

561

569

583

Contents

38.3 Starting Protocol Software 584 38.4 Protocol Parameters 584 38.5 Protocol Configuration 585 38.6 Examples Of Items That Need To Be Configured 585 38.7 Example Configuration: Using A Disk File 586 38.8 The Need To Automate Protocol Configuration 587 38.9 Methods For Automated Protocol Configuration 587 38.10 The Address Used To Find An Address 588 38.11 A Sequence Of Protocols Used During Bootstrap 589 38.12 Bootstrap Protocol (BOOTP) 589 38.13 Automatic Address Assignment 591 38.14 Dynamic Host Configuration Protocol (DHCP) 592 38.15 Optimizations In DHCP 593 38.16 DHCP Message Format 593 38.17 DHCP And Domain Names 594 38.18 Summary 595

xxiii

Appendix 1 Glossary Of Networking Terms And Abbreviations 597

Appendix 2 The ASCII Character Set 637

Appendix 3 Address Masks In Dotted Decimal 639

Appendix 4 How To Use The CD-ROM Included With This Book 641

Appendix 5 Building A Network At Home With NAT 647

Appendix 6 The Undergrad Networking Lab At Purdue 653

Bibliography 659

Index 667

Index

Constants and numeric items

0800 132 ,1OBase2 145

1OBase5 142 10BaseT 146,598 125 J.lseconds 174 125 seconds 182 127 address 294 128 Kbps 183 13 Mbps 187 1962 173 2-3 swap 61, 598 2-wire 72 200 498 2430 octets 182 26 Mbps 187 2B+D 183 2B+D service 598 3-way handshake 369, 598 3-wire circuit 598 32 Kbps 186 4-wire 72 4-wire circuit 598 4.1325 KHz 186 404 498 5-layer reference model 276 52 Mbps 187 56 Kbps 179 576 Kbps 185 6.144 Mbps 185 6.4 Mbps 186

64 Kbps 183 640 Kbps 185, 186 7-layer reference model 249,598 8-bit sample 174 802.11 110 802.2 132, 598 802.3 598 802.5 599 810 octets 182

A

A-to-D converter 174 AAL5 226,599 ABR 225 Abstract Syntax Notation. 1 564,601 Abstract Window Toolkit 535, 601 accept 418 access delay 241, 599 accountability 571 ACK 257 acknowledgement 257,365,599,623 active document 510,529, 599 Active Server Pages 523 actual arguments 551 adaptive 95,186,366 adaptive bridge 161 Adaptive Pulse Code Modulation 175 adaptive retransrnission 599 add/drop mux 182 address 192,599

all ones 293

I1 I"

668

all zeroes 293,294 destination 161 loopback (127) 294 network prefix 293 protocol 302 source 161

address binding 303 address class 284 address mask 290, 321, 587, 599, 639 Address Mask Reply 354 Address Mask Request 354 address parameter 584 address resolution 301, 302, 599, 600

closed-form 305 message exchange 306 table lookup 304

Address Resolution Protocol 307 addressing scheme 237 ADSL 184, 600 Advanced Research Projects Agency 8,

212, 275 Advanced Window Toolkit 535 AF_INET 416 agent 563 AirLAN 110 Airport 110 all ones address 293 all ones suffix 293 all zeroes address 294 all zeroes suffix 293 Alternative Window Toolkit 535 AM 68 amplitude modulation 68 analog-to-digital converter 174 anal yzer 13 3 anchor 496 anonymous 477 anonymous FTP 477, 600 answer mode 72 antenna 193 anycast 347 APCM 175, 194, 600 API 19,411,412, 600, 630 applet 531,600

applet tag 540 Applet Widget Toolkit 535 AppleTalk 253, 600

Index

Application Program Interface 19, 412 application-layer gateway 577,600 applications 17 area 388, 600 argc 25 arguments 551 argv 25 ARP 307,600 ARP cache 311 ARPA 8,212,275 ARPANET 8,212 AS 379,600 ASCII 84, 479, 601 ASCII standard 57 ASN.1 564, 601 ASP 523,601 Asymmetric Digital Subscriber Line 184 asynchronous 56, 175, 244, 601 asynchronous communication 55 Asynchronous Transfer Mode 115, 214,

218,270 ATM 115, 214, 218, 239, 270, 601

Adaptation Layer 5 226· VPIIVCI 221 cell header 219 segmentation and reassembly 226 switch 221

Attachment Dnit Interface 143 AUI 143, 156, 601

cable 143 connector 143

authentication 572 authoritative answer 448 authority for naming 444 authorization 571 automatic garbage collection 533 automatic routing see dynamic routing Autonomous System 379 availability 571 Available Bit Rate 225 AWT 535,601

-

Index

B

B channel 183, 601 backoff 109 bandwidth 62,241,601 base header 342, 601 baseband technology 75,602 Basic Rate Interface 183 batch 473 baud 64,602 baud rate 59, 70 Bearer 601 Berkeley broadcast 295 Berkeley Software Distribution 295 best-effort 323, 602 BGP 382,602 bidding 591, 602 big endian 559 bin 513 binary exponential backoff 109, 602 binary representation 530 bind 415 bit stuffing 85, 113, 177 bits per second 241 blind carbon copy 459 blocking 434 bluetooth 110 BNC connector 145,602 body 457,491 bonded 183 bookmark 505 booting 583 BOOTP 589, 602 bootstrap 484, 602 BOOTstrap Protocol 589 Border Gateway Protocol 382 box 152 bps 241,602 BREAK 59 BR! 183,602 bridge 160, 603

adaptive 161 address 167 satellite 164

bridge tap 187 broadband technology 75,603 broadcast 125, 192,227,233, 603 broadcast address 126, 130, 603 broadcast satellite 192, 603 browser 489,603 BSD UNIX 295, 475 buffering 165 burst error 93 bus in a box 150 bus topology 105, 603 byte stuffing 85,603 bytecode 533

C

C++. 532 cable see wire cable modem 603 cable television 188 cable termination 144 cache 311,502 caching 449, 501, 502 calling mode 72 capacity 259 carriage control 475 carriage return 476, 498 carrier 68, 108, 604 carrier sense 108, 111

669

Carrier Sense Multiple Access 108, 606 category 5 cable 604 CATV 188, 604 CBR 225 CBT 391,604 CCITT 213,604 CD 109 CD-ROM 641 CDm 114, 604 cell 219,604 cell tax 220, 227, 604 Central Office 183 CGI 513,524,604 CGI program 513 CGI-bin 513

670

channel 48, 186 Channel Service Unit 176 character 57 character stuffing 85 CHARGEN 436 chat 29,604 chatclient in chatclient.c 32 chatserver in chatserver.c 30 checksum 89, 571, 604 Chicago 173 CIDR 605 CIDR notation 291,639 CL 235,605 class 284 classful addressing 605 classful IP addressing 284 classless addressing 289, 605 clear to send 60 client 18,399,605 client-server paradigm 18, 399, 605 client.c 428 clocked 175 close 413, 415, 422 closesocket 415, 436 cluster 347, 605 CNAME 450 CO 183, 235, 605 coax 46 coaxial cable 46, 605 code 540 codebase 540 ColdFusion 523, 606 collaboration 340 collision 108, 606 collision avoidance 111 collision detection 109,607 colon hex 348 colon hexadecimal notation 348, 606 color division multiplexing 75 column (SONET) 182 COM 558 Common Gateway Interface 513,524,

604

Index

Common Object Request Broker Architecture 557

communication paradigm 19 communication stub 554 Community Antenna TeleVision 188 compiler 530 Component Object Model 558 computer communication protocol 248 concatenated 181 concurrency 403 concurrent program 403, 532 conditional get 506 confidential 235, 572 confidentiality 571 configurable addressing scheme 124 configured 585 congestion 242,263,606 congestion collapse 263, 370 congestion control 370 connect 418

. connection 220 connection duration 236 connection identifier 239 connection multiplexors 144 connection-oriented 217, 220, 235, 236,

317,405,606 connectionless 235,237,317,405,606 connector

DB-25 60 RJ-45 147

Constant Bit Rate 225 control connection 476 cookie 517, 606 copper .45 . Copper Distributed Data

Interconnection 114 CORBA 557 core 391 counter rotating 114, 182 cover page 644 CPU 139 CRC 90, 92, 255, 606 CRLF 36,498 cryptographic hashing 572

c

Index

CSMA 108,111,607 CSMAJCA 111 CSMAJCD 109,607 CSU 176 current 56 cycles per second 62 cyclic redundancy check 90, 255, 571,

606

D

D channel 183, 607 D-to-A converter 174 DARPA 8 data area 128 4ata availability 571 Data Communication Equipment 61 data confidentiality 571 data connection 483 data integrity 571 Data Service Unit 176 data stuffing 85 Data Terminal Equipment 61 datagram 634 DAYTIME 435 dB 63 DB-25 60, 607 DB-9 65 DCE 61,557 DCEIRPC 557 DCOM 558 decibels 63 default route 206, 321, 376, 384, 607 delay 240, 259, 381 delay-bandwidth product 243, 607 delay-throughput product 243 demodulator 70,607,620 demultiplex 607 denial-of-service 14, 607 Dense Wave Division Multiplexing 75 descriptor 413 destination 282,576 DESTINATION ADDRESS 342 destination address 122, 607

DESTINATION PORT 405 destination umeachable 354 DHCP 592, 608 dialup modem 72, 608 dictionary 535

. digital audio 174 Digital Equipment Corporation 557 Digital Signal Level standards 178 digital signature 573, 608 Digital Subscriber Line 184 digital-to-analog converter 174 digitization 174 Direct Memory Access 141 directed broadcast 608 directed broadcast address 293 Discrete Multi Tone modulation 186 dish antenna 193 distance 209 distance-vector 209, 384, 608 Distributed Component Object

Model 558

671

Distributed Computing Environment 557 distributed route computation 209 distributed spanning tree 167, 608 DIX Ethemet 106, 608 DMA 141 DMT 186 DNS 439, 440, 608 DNS reply 448 DNS request 448 Document Object Model 545 DOM 545 domain 608 Domain Name System 440,608 dotted decimal notation 286, 609 downlink 609 downstream 184,609 DS standards 178 DS-1, DS-3 609 DSL 184,609 DST 167 DSU/CSU 176,609 DTE 61 dual path 189

672

duplication 257 DV 609 DVMRP 391, 609 DWDM 75 dynamic 532 dynamic addressing scheme 124 dynamic document 510, 609 Dynamic Host Configuration

Protocol 592 dynamic routing 207,375,377

E

e-mail 455, 609 body 457 header 457

e-mail address 456 e-mail gateway 463 e-mail interface 461. e-mail relay 463 El 178 E2 178 E3 178 EBCDIC 479,610 echo application 23 echo cancellation 219 echo reply 354, 610 echo request 354, 610 echoclient in echoclient.c 26 echo server in echoserver.c 24 ECMA script 543 edge 205 edge triggered 106 effective throughput 241 EGP 380,610 EIA 57 , electro-magnetic interference 87 Electronic Industries Association 57 electronic mail 455, 609 electronic mail address 456 encapsulation 310, 330, 610 encode 459 encryption 235, 572 encryption key 572, 610

end of transmission 84 end-of-file 19 end-to-end 363, 506, 610 endpoint address 418, 610 environment variables 516 eot 84 error 93 error handling 543 ether 106 Ethernet 106, 238, 610

lOBase5 142 AUI 143, 156 BNC connector 145 broadcast address 130 frame 129, 130 hub 146 multicast address 130 repeater 157 segment 158 thick wire 142 thin cable 145 topology 150 types 130

even parity 88, 611 exception 535,543 exclusive or 90 executable representation 531 explicit frame type 128 exponential backoff 109 Extensible Markup Language 504 extension header 342, 611 Exterior Gateway Protocol 380 exterior switch 204,611 externaLdatarepresentation 555, 556

F

factory 536 falling edge 106 family 248 Fast Ethernet 106, 611 favorite 505 FDDI 114, 238, 611

counter rotating ring 169

Index

Index

FDDI hub 169 FDM 74,611 feeder circuit 190, 611 fetch 487 fetch-store paradigm 564 fiber 114, 611 Fiber Distributed Data Interconnect 114 fiber modem 156, 611 Fiber Optic Intra-Repeater Link 158 fiber optics 47 Fiber To The Curb 191 field 122 file access 485 file transfer 471, 472

see FTP File Transfer Protocol 474 FIN segment 369 fine-grain 225 firewall 574 flooding 14 flow control 258, 611 FLOW LABEL 343 FM 68 FOIRL 158 form 522 formal parameters 551 forward 612 forwarding 322 forwarding table 221 fractional T1 179 fragment 612 fragmentation 333, 345, 612 frame 84,612

data area 128 explicit type 128 header 128 implicit type 128 payload 128 preamble 129 self-identifying 128 type 129,130, 131 type field 128

frame checksum 255 frame filtering 161

Frame Relay 213, 238, 612 frame type 311 framing error 59, 612 frequency 48

673

frequency division multiplexing 74, 186, 612

frequency modulation 68 FTP 474,612 FTP commands 475 FTTC 191, 612 full duplex 60, 70, 236 full-duplex transmission 612

G

Gbps 106,241,612 general purpose 532 GEO 49,612 Geostationary Earth Orbit 49 geostationary satellite 49 geosynchronous satellite 49 GET (HTTP) 36, 498 gethostbyaddr 421 gethostbyname 421,448 gethostname 421 getpeername 421, 437 getsockopt 421 GIF 495,613 Gigabit Ethernet 106,613 global Internet 275 graphics 533, 534 graphics interchange format 495

see GIF graphics toolkit 535 ground 60 guest 477

H

half duplex 60, 72 half-duplex transmission 613 Hand-held Device Markup Language 503 hardware address 122, 301, 613 hashing 572 HDML 503

1

674

HDSL 187,613 HDSL2 187 HEAD 498 head 491 header 122, 128, 457

base 342 extension 342 options 344

Hertz 62, 613 HFC 190,613 hierarchical addressing 201, 613 high earth orbit 49 high level 532 high speed 240 High-Rate Digital Subscriber Line 187 home network 647 homepage 490, 613 hop 14,202,384,385,614 hop count 381,614 HOP LIMIT 343 hop limit 614 host 277, 614 HTML 491, 614 HTTP 498, 614 HTTP-NG 503 HTTPS 503 hub 104,153,614 Hybrid Fiber Coax 190 hypermedia 490, 614 hypertext 490,614 HyperText Markup Language 491 HyperText Transfer Protocol 498 Hz 62

I

I/O on a network 534 IANA 614 IBM Token Ring 114, 615 ICANN 441 ICMP 352, 587, 615

type 353 ICS 615,649 IDL 556

IEEE 57,132 802.2 132 LLC/SNAP header 132 registration authority 136

IGMP 389, 615 !GP 380,615 IIS 523 IMG tag 495 IMP 212 import 538 INADDR_ANY 417 infrared 51 Institute for Electrical and Electronic

Engineers 57 instruction pointer 537

Index

Integrated Services Digital Network 183 integrity 571 interactive TV 190 Interface Definition Language 556 interface hardware 139 Interface Message Processor 212 interface paradigm 235 Interior Gateway Protocol 380 interior switch 204, 615 International Organization for

Standardization 249 International Telecommunications

Union 57 Internet 8,275,615 Internet access 533 Internet address 282, 615 Internet Assigned Number Authority 288 Internet Connection Sharing 649 lnternet-Control Message Protocol 352 Internet firewall 574, 615 Internet Group Multicast Protocol 389 Internet Information Server 523 Internet Layering Model 276 Internet Protocol 275, 282, 616 Internet Protocol address 282 Internet reference model 276, 615 internet routing 375 Internet Service Provider 288, 617 internetwork 271

Index

intemetworking 8,271 Interpretative Execution 533 c

interpreter 533 Intersymbol Interference 62 intranet 616 inverse multiplexing 186 inverse multiplexor 179 IP 282,616 IP address 282, 616 IP datagram 319, 616 IP options 325 IP switching 616 IP tunnel 579, 616 IP-in-IP 390, 579, 616 iplnReceives 565 IPng 341, 616 ipRouteNextHop 566 IPv4 341, 616 IPv6 341, 616 IPX 130,616 ISDN 183, 194, 218, 617 ISO 249,617 isochronous 175,244,617 ISP 288,617 iterative query resolution 449 ITU 57,212,617

J

Java 531,617 Java bytecode representation 533 Java compiler 537 Java Programming Language 531 Java RMI 552 Java Server Pages 523 javac 537 JavaScript 543, 617 jitter 218,244,381,617 JSP 523,617

K

Kbps 111, 617 Kepler's Law 49 key 572,573

keyword 457

L

lab 653 label switching 221,618 LAN 102, 197, 618 laser 47, 52 layer 249 layer-3 switching 618 layering 313 layering model 249, 618 layering principle 254 learning bridge 161 lease 593 leased serial line 71 LED 47 LEO 50,618 library 531, 534 light emitting diode 47 lightning 87 limited broadcast 293 limited broadcast address 293 linefeed 476, 498 link 205 link-state

see link-status link-status 387 link-status routing 212, 618 list manager 464 listen 417 little endian 559 LLC 132,618 Local Area Network 102, 197, 618 local loop 183, 618 local subscriber line 183 localhost 426

675

locality of reference 102, 103,447, 502, 619

LocalTalk 111,619 wiring 152

Logical Link Control 132, 618 long-haul network 197,619

also see WAN

]

676

loopback 177 loopback address 294,619 loss 257 Low Earth Orbit 50 low speed 240 '

M

MAC 572 MAC address 122 mail exploder 462, 619 mail forwarder 462 mail gateway 463 mail transfer 461 mailer 469 mailing list 462 MAN 197 Management Information Base 565, 620 manager 563 Manchester Encoding 106 MARK 58 markup language 491 marshaling 554 mask 290, 619 Masquerade 619, 649 maximum transmission unit 332, 620 MBONE 391, 619 Mbps 106, 241, 619 media 45 media access address 122 mesh network 100, 620 message authentication code 572 message exchange 306 ,message interface 237 message type (DHCP) 594 method 532, 556 method invocation 556 Metropolitan Area Network 197 MIB 565,620 microkemel 533 microsecond 174 Microsoft 557 middleware 556 MIME 460, 620

modem 61,70,620 2-wire 72 4-wire 71, 72 RP 72 dialup 72 fiber 156 leased line 71 optical 72

Modula-3 552 modulation 68, 70, 186, 620

amplitude 68 frequency 68 phase shift 69

modulator 70, 620 monitor 133 MOSPF 391, 620 mrouted 391,620 MSRPC 557 MSRPC2 557 MTU 332, 346, 620 multi-homed 383 multi-homed host 297 multicast 127, 347, 620

bridge address 167 multicast address 127, 130 Multicast backBONE 391 multicast routing 389 multihomed 621 multiplex 621 multiplexing

color division 75 frequency division 74 time division 76, 83, 183 wave division 75

multiplexor add/drop 182 inverse 179

Multipurpose lIitemet Mail Extensions 460

multithreaded execution 533

N

name resolution 447

Index

Index

name resolver 447 naming 439 naming authority 444 NAT 621,647 National Center for Supercomputer

Applications 513 National Science Foundation 275 NBMA 227 NCSA 513 Netware 253, 621 network adapter 621 network adapter card 140 network address 293 Network Address Translation 647 network analyzer 133, 621 Network File System 485,622 network hardware 139 network I/O 534 network in a box 150 network interface card 140, 622 network interface layer 313 network management 621 network management software 563 network manager 561 network monitor 133,621 network node 205 network number 283 network programming 17 network protocol 248 network sniffer 133 NEXT HEADER 343 next header 621 nexthop 209,302,585 next-hop forwarding 202,622 NFS 485,622 NlC 140,622

connectors 142 node 205,622 noise 62 Non Broadcast Multiple Access 227 non-self referential 677 nslookup 453 null modem 61 Nyquist 62

Nyquist Sampling Theorem 622

o object 556 object oriented 532 Object RPC 557 object-oriented 556 object-oriented paradigm 556 OC 181,622 OC-3 622 odd parity 88, 622 ONC RPC 556 one way property 573 one-arm router 623 ONU 187 open 413 Open Group 557 Open Network Computing 556 Open Shortest Path First Protocol 386 Open Software Foundation 557 open-read-write-close 413 Optical Carrier 181 optical fiber 47, 623 optical modem 72, 623 Optical Network Unit 187 options (IP) 325 options (IPv6) 344 order 255

677

Organizationally Unique Identifier 132 origin server 502 ORPC 557 OSPF 386, 623 OUI 132,623 out of order 255 ownership 232

p

packaging scheme (COM) 558 packet 81, 83, 84,623

data area 128 duplication 257 header 128 loss 257

678

order 255 payload 128

packet filter 576, 623 packet network 81 packet switch 198 ~

packet switching network 8, 81, 623 page 490 PAR 623 parallel transmission 57 parameter problem 354 parameterized 551, 584 parity bit 88, 255, 624 passive RIP 384 password 572 path MTU 337,346,358,624 payload 128, 624 PAYLOAD LENGTH 343 PCM 175,624 performance analyzer 133 Perl Helper Pages 523 permanent 236 permanent virtual channel 223 permanent virtual circuit 238, 626 persistent connections 503 PF_INET 415 phase shift 624 phase shift modulation 69 PHP 523,624 physical address 122, 161, 301, 624 physical locality 103 PIM-DM 391, 624 PIM-SM 391, 624 ping 11, 356, 624 pipe 414 Plain Old Telephone Service 183 PLAY32 642 plug-and-play networking 592, 625 plugin 642 point and click 489 point-to-multipoint 227, 625 point-to-point circuit 176 point-to-point network 100, 625 Point-to-Point Protocol 85 pointer query 453

policy constraint 380 polynomial 93 POP 467 port 147, 168, 221 positive acknowledgement with

retransmission 257 POST 498 Post Office Protocol 467 POTS 183 PPP 85 preamble 107, 129 PRI 625 primary class 284 privacy 235, 571 private 233 private key 573 private network 232,235, 578 probability 89 procedure call 550 procedure call graph 550 process 403 program interface 600 programming (network) 17 promiscuous mode 133,625,656 prompt 474 propagation delay 240, 625 protocol 248, 625 protocol address 302, 625 protocol configuration 585, 625 protocol family 248 protocol independent 391 protocol port number 403, 626 protocol software 248 protocoLsuite 248, 626 provisioned 223,626 proxy 554, 577 prune 391 public 463, 537 public Internet 275 public key 573 public network 232 Pulse Code Modulation 175, 624 PUT 498 PVC 223, 238, 626

Index

Index

Q

QoS 225,626 quality of service 225 QUERY_STRING 516 queuing delay 241,626 QuickTime 642 quiet mode 482

R

Radio Frequency 48, 72 RangeLAN 110 RARP 587,626 rate control 263 read 413,414,421 Read-Only Memory 484 reassembly 226,334,345,626 reboot 565 recursive query resolution 449 recv 420 recvfrom 420 recvmsg 420 redirect 354, 626 redirection 513 redundancy check 90 reference count 422 relay agent 596 reliable 257 remote 553 remote file access 471 Remote Procedure Call 550 repeater 157, 158 replay 258, 627 replication 449 Request For Comments 15 reserved address (IP) 293 reset 565 resolved 302 retransmission 257, 365, 627 Reverse Address Resolution Protocol 587 Reverse Path Broadcast 390 RP 48,627 RP modem 72, 627 RPC 15

ring see IBM Token Ring ring in a box 152 ring network 112, 114, 182 ring topology 104, 627 RIP 384,627 rising edge 106 RJ-45 147, 627 root server 444, 627 round-robin 76 round-trip delay 366 route 207 route propagation 627 route propagation software 375 route server 383,627 routed 384, 628 router 14, 271, 628 router discovery 587 routing 203, 322, 375 routing arbiter system 383, 628 Routing Information Protocol 384 routing metric 381 routing table 203, 320, 628 row (SONET) 182 RPB 390 RPC 550,556 RS-232 55, 57, 628 RS-422 57 RS-449 177 runtime environment 531

s sampling theorem 174 satellite 164, 192 sajarnily 416 sa_len 416 scalability 198 SDH 181 SDSL 187 secret 573 secret key 572 secure perimeter 575 secure proxy 577, 628 security policy 570

679

680

segment 106, 158, 370, 628 segmentation 226 segmentation and reassembly 628 selectable 490 self-healing network 115, 628 self-identifying 128, 285 send 419 sequencing 255 serial 57 serial data circuit 71 serial line 71, 628 server 18, 399, 534, 629 server push 528 Server Side Include 525 server-class computer 400 server.c 431 service guarantees 218, 237 service paradigm 235 session 276 session cookie 517, 629 setsockopt 421 Shannon's Theorem 62 Shannon-Hartley Law 62 shape 103 shared channel 102 SHDSL 187 shielded twisted pair 47,629 shift register 90, 91 ShockWave 642 shortest path 207 Shortest Path First 212, 630 signal 586 signal loss 67, 629 signal-to-noise ratio 63 signaling 224 Simple Mail Transfer Protocol 462 Simple Network Management

Protocol 564 Simple Player 642 simplex communication 60, 236 skeleton 523 slash notation 629, 639 sliding window 259,629 Slotted Time Division Multiplexing 76

slow start 372 SMDS 213, 238, 629 SMTP 462, 629 SNAP 132, 630 sniffer 133, 630 SNMP 564, 630 snoop 656 sockaddr 416 sockaddr_in 416 socket 411,412,414,415,533 socket API 412,630 SOCK_DGRAM 415 SOCK_STREAM 415 soh 84 Solaris 428 SONET ring 181, 182 source 282, 576 SOURCE ADDRESS 342, 585 source address 122, 630 source independence 203 SOURCE PORT 405 Source Quench 353 source representation 530 SPACE 58 spatial locality 103 speed 139, 241 SPF 212,630 spread spectrum 76, 630 SSI 525 ST 341 stability 388 stack 252, 630 standards bodies 57, 503 star 115 star topology 103, 630 star-shaped bus 150, 153 star-shaped ring 153 start bit 58 start of header 84 state information 517 stateful server 631 stateless server 631 static addressing scheme 124 static document 510, 631

Index

Index

static routing 207,375,376 static type checking 532 station 122 statistical multiplexing 76,631 STDM 76,631 stop bit 58 stop-and-go 258 store and forward 200, 631 stream interface 237 STS 180,631 stub 383 stuffing 177 subchannels 186 subnet addressing 289, 631 sllbnet mask 290,587,631,639 SubNetwork Attachment Point 132 subscriber loop 183 sudo 656 suite 248, 631 Sun Microsystems 556 Sun RPC 556 SVC 224,632 switch 221, 632 Switched Multi-megabit Data

Service 213, 238 switched network 168, 194, 236, 632 Switched Virtual Channel 224 switched virtual circuit 238, 631 switching 168, 632 switching delay 241 switching system 224 Symmetric Digital Subscriber Line 187 SYN segment 369 synchronization segment 369 synchronized 175 synchronous 56, 175,434,632 Synchronous Digital Hierarchy 181 Synchronous Optical NETwork 181 Synchronous Time Division

Multiplexing 76 Synchronous Transport Signal 180

T

T -series standards 177 Tl 177, 178, 186,632 T2 178 T3 178,632 table lookup 304, 305 tags 491 target 310 task 403 TCP 362, 403, 556, 632 TCP/IP 275, 632 TCP/IP Internet Protocols 275 TCP/IP layering model 276 TDM 76, 179, 633 telnet 435 template 523 temporal locality 103 TENEX 475 terminator 144,633 TFTP 484, 591, 633 thick wire Ethernet 142, 633 Thicknet 142,633 thin wire Ethernet 145,633 Thinnet 145, 633 this computer address 294 three wire circuit 60 throughput 241, 259, 381, 633

681

time division multiplexing 76, 83, 179, 183,633

Time Exceeded 354 time of day 586 token 113 token passing 112, 633 Token Ring 238

see IBM Token Ring token ring 112,614, 633 tool 550 top-level domain 440 topology 103, 139, 634

bus 105, 106, 107 hub 104 mesh 100 point-to-point 100

682

ring 104, 112, 114, 182 star 103, 115

TP Ethernet 146,634 traceroute 14, 356, 634 tracert 357 traffic class 342 transceiver 143, 153, 156, 634 transit 383 Transmission Control Protocol 362, 632 transmission error 87, 634 transmission media 45 transponder 48 tree 167 Trivial File Transfer Protocol 484 trunk 180, 190 trunk circuit 634 TTL 634 tunnel 390, 579, 634 twisted pair 46, 634 twisted pair Ethernet 146, 634 type 129, 353, 450 type Applet 539 type Exception 543 type field 311 type in frames 130

U

lnDP 357,405,556,635 unicast 347,635 unicast address 126 Uniform Resource Locator 495, 635 universal function 423 universal packet 318 universal service 218,270 UNIX 428, 475 unordered list 494 unreachable 354 uplink 192, 635 upstream 184, 635 URL 495,635 User Datagram Protocol 357,405 utilization 242

V

V.35 177 Variable Bit Rate 225 VBR 225 VC 220,635 VCI 221 VDSL 187 vector-distance 635 VERS 342 vertical error 93 Very-high bit rate Digital Subscriber

Line 187 video on demand 190 virtual channel 220, 635 Virtual Channel Identifier 221 virtual circuit 221

also see virtual channel virtual connections 363 virtual network 273 virtual packet 318 Virtual Path Identifier 221 Virtual Private Network 234, 578

Index

Vo~ce Extensible Markup Language 503 V OlceXML 503 voltage 57 VPI 221 VPIIVCI 221, 635 VPN 234, 578, 635

W

WAN 197,636 W AP _ 503, 636 W AP Markup Language 503 wave division multiplexing

seeWDM waveform diagram 57 WaveLAN 110 WDM 78 Web 636 Web document 510 webclient.c 34 webserver.c 36 Web site 641

Index

weight 207 Wide Area Network 197, 635 wildcard 478 window 367,368,636 window advertisement 368 window size 259 Windows NT 428 Windows Sockets 415 wire 45

coaxial 46 Wireless Access Protocol 503 wireless LAN 110 wireless networking 72 wiring 152 WML 503 World Wide Web 489,636 write 413,414,421 WWW 489,636

x X Window System 536 X.25 131 XDR 556,559 xDSL 184,636 XML 504,636 xor 90 xv 642

z zero compression 348, 636 zero window 368

683