Data Communication
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DATA COMMUNICATIONS AND NETWORKING
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McGraw-Hill Forouzan Networking Series
Titles by Behrouz A. Forouzan: Data Communications and Networking TCP/IP Protocol Suite Local Area Networks Business Data Communications
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DATA COMMUNICATIONS AND NETWORKING
Fourth Edition
Behrouz A. Forouzan
DeAnza College
with
Sophia Chung Fegan
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New copyright page to come
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To my wife, Faezeh, with love Behrouz Forouzan
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BRIEF CONTENTS
Preface PART 1
xxix Overview Introduction 1 3 27 55
Chapter 1 Chapter 2 PART 2 Chapter 3 Chapter 4 Chapter 5 Chapter 6 Chapter 7 Chapter 8 Chapter 9 PART 3 Chapter 10 Chapter 11 Chapter 12 Chapter 13 Chapter 14 Chapter 15 Chapter 16 Chapter 17 Chapter 18
Network Models
Physical Layer and Media Data and Signals 57 101 141 Digital Transmission Analog Transmission Transmission Media Switching 213
Bandwidth Utilization: Multiplexing and Spreading 191
161
Using Telephone and Cable Networks for Data Transmission 241 Data Link Layer Data Link Control Multiple Access Wireless LANs 265 267 307 395
Error Detection and Correction 363 421
Wired LANs: Ethernet
Connecting LANs, Backbone Networks, and Virtual LANs 445 Wireless WANs: Cellular Telephone and Satellite Networks 467 SONET/SDH 491 517 vii Virtual-Circuit Networks: Frame Relay and ATM
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BRIEF CONTENTS
PART 4 Chapter 19 Chapter 20 Chapter 21 Chapter 22 PART 5 Chapter 23 Chapter 24 PART 6 Chapter 25 Chapter 26 Chapter 27 Chapter 28 Chapter 29 PART 7 Chapter 30 Chapter 31 Chapter 32 Appendix A Appendix B Appendix C Appendix D Appendix E Appendix F Appendix G Appendix H Acronyms Glossary References Index 1111
Network Layer
547 549 579
Network Layer: Logical Addressing Network Layer: Internet Protocol
Network Layer: Address Mapping, Error Reporting, and Multicasting 611 Network Layer: Delivery, Forwarding, and Routing Transport Layer 701 703 761 647
Process-to-Process Delivery: UDP, TCP, and SCTP Congestion Control and Quality of Service Application Layer 795 797
Domain Name System WWW and HTTP Multimedia Security 901 851
Remote Logging, Electronic Mail, and File Transfer Network Management: SNMP 873
817
929 931 961
Cryptography
Network Security
Security in the Internet: IPSec, SSL/TLS, PGP, VPN, and Firewalls 995 Unicode 1029 1037 1043 Numbering Systems Mathematical Review 8B/6T Code 1055 1059 1061 1065 Telephone History Contact Addresses RFCs 1063 UDP and TCP Ports
1067 1071 1107
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CONTENTS
Preface
xxix Overview 1 3
3
PART 1
Chapter 1
1.1
Introduction
DATA COMMUNICATIONS
Components 4 Data Representation Data Flow 6 5
1.2
NETWORKS
7
Distributed Processing 7 Network Criteria 7 Physical Structures 8 Network Models 13 Categories of Networks 13 Interconnection of Networks: Internetwork
15
1.3 1.4
THE INTERNET
16 19
A Brief History 17 The Internet Today 17
PROTOCOLS AND STANDARDS
Protocols 19 Standards 19 Standards Organizations Internet Standards 21 20
1.5
RECOMMENDED READING
Books 21 Sites 22 RFCs 22
21
1.6 1.7 1.8
KEY TERMS 22 SUMMARY 23 PRACTICE SET 24
Review Questions 24 Exercises 24 Research Activities 25
Chapter 2
2.1
Network Models
27
28
27
LAYERED TASKS
Sender, Receiver, and Carrier Hierarchy 29
ix
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CONTENTS
2.2
THE OSI MODEL
29
Layered Architecture 30 Peer-to-Peer Processes 30 Encapsulation 33
2.3
LAYERS IN THE OSI MODEL
Physical Layer 33 Data Link Layer 34 Network Layer 36 Transport Layer 37 Session Layer 39 Presentation Layer 39 Application Layer 41 Summary of Layers 42
33
2.4
TCP/IP PROTOCOL SUITE
Physical and Data Link Layers Network Layer 43 Transport Layer 44 Application Layer 45
42
43
2.5
ADDRESSING
45
Physical Addresses 46 Logical Addresses 47 Port Addresses 49 Specific Addresses 50
2.6
RECOMMENDED READING
Books 51 Sites 51 RFCs 51
50
2.7 2.8 2.9
KEY TERMS 51 SUMMARY 52 PRACTICE SET 52
Review Questions 52 Exercises 53 Research Activities 54
PART 2
Physical Layer and Media Data and Signals
57
58
55
Chapter 3
3.1
57
ANALOG AND DIGITAL
Analog and Digital Data 57 Analog and Digital Signals 58 Periodic and Nonperiodic Signals
3.2
PERIODIC ANALOG SIGNALS
59
3.3
Sine Wave 59 Phase 63 Wavelength 64 Time and Frequency Domains 65 Composite Signals 66 Bandwidth 69 DIGITAL SIGNALS 71 Bit Rate 73 Bit Length 73 Digital Signal as a Composite Analog Signal Transmission of Digital Signals 74
74
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CONTENTS
xi
3.4
TRANSMISSION IMPAIRMENT
Attenuation 81 Distortion 83 Noise 84
80
3.5
DATA RATE LIMITS
85
Noiseless Channel: Nyquist Bit Rate 86 Noisy Channel: Shannon Capacity 87 Using Both Limits 88
3.6
PERFORMANCE
89
Bandwidth 89 Throughput 90 Latency (Delay) 90 Bandwidth-Delay Product Jitter 94
92
3.7 3.8 3.9 3.10
RECOMMENDED READING
Books 94
94
KEY TERMS 94 SUMMARY 95 PRACTICE SET 96
Review Questions Exercises 96 96
Chapter 4
4.1
Digital Transmission
101
101
DIGITAL-TO-DIGITAL CONVERSION
Line Coding 101 Line Coding Schemes Block Coding 115 Scrambling 118 106
4.2 4.3 4.4 4.5 4.6 4.7
ANALOG-TO-DIGITAL CONVERSION
Pulse Code Modulation (PCM) Delta Modulation (DM) 129 121
120
TRANSMISSION MODES
Parallel Transmission 131 Serial Transmission 132
131 135
RECOMMENDED READING
Books 135
KEY TERMS 135 SUMMARY 136 PRACTICE SET 137
Review Questions Exercises 137 137
Chapter 5
5.1
Analog Transmission
141
141
142
DIGITAL-TO-ANALOG CONVERSION
Aspects of Digital-to-Analog Conversion Amplitude Shift Keying 143 Frequency Shift Keying 146 Phase Shift Keying 148 Quadrature Amplitude Modulation 152
5.2
ANALOG-TO-ANALOG CONVERSION
Amplitude Modulation 153 Frequency Modulation 154 Phase Modulation 155
152
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CONTENTS
5.3 5.4 5.5 5.6
RECOMMENDED READING
Books 156
156
KEY TERMS 157 SUMMARY 157 PRACTICE SET 158
Review Questions 158 Exercises 158
Chapter 6
6.1
Bandwidth Utilization: Multiplexing and Spreading 161
161
MULTIPLEXING
Frequency-Division Multiplexing 162 Wavelength-Division Multiplexing 167 Synchronous Time-Division Multiplexing 169 Statistical Time-Division Multiplexing 179
6.2 6.3 6.4 6.5 6.6
SPREAD SPECTRUM
180
181
Frequency Hopping Spread Spectrum (FHSS) Direct Sequence Spread Spectrum 184
RECOMMENDED READING
Books 185
185
KEY TERMS 185 SUMMARY 186 PRACTICE SET 187
Review Questions 187 Exercises 187
Chapter 7
7.1
Transmission Media
192
191
GUIDED MEDIA
Twisted-Pair Cable 193 Coaxial Cable 195 Fiber-Optic Cable 198
7.2
UNGUIDED MEDIA: WIRELESS
Radio Waves 205 Microwaves 206 Infrared 207
203
7.3 7.4 7.5 7.6
RECOMMENDED READING
Books 208
208
KEY TERMS 208 SUMMARY 209 PRACTICE SET 209
Review Questions Exercises 210 209
Chapter 8
8.1
Switching
213
214
CIRCUIT-SWITCHED NETWORKS
Three Phases 217 Efficiency 217 Delay 217 Circuit-Switched Technology in Telephone Networks
218
8.2
DATAGRAM NETWORKS
Routing Table 220
218
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CONTENTS Efficiency 220 Delay 221 Datagram Networks in the Internet
xiii
221
8.3
VIRTUAL-CIRCUIT NETWORKS
221
Addressing 222 Three Phases 223 Efficiency 226 Delay in Virtual-Circuit Networks 226 Circuit-Switched Technology in WANs 227
8.4 8.5 8.6 8.7 8.8
STRUCTURE OF A SWITCH
Structure of Circuit Switches 227 Structure of Packet Switches 232
227 235
RECOMMENDED READING
Books 235
KEY TERMS 235 SUMMARY 236 PRACTICE SET 236
Review Questions Exercises 237 236
Chapter 9
9.1
Using Telephone and Cable Networks for Data Transmission 241
241
TELEPHONE NETWORK
Major Components 241 LATAs 242 Signaling 244 Services Provided by Telephone Networks
247
9.2 9.3
DIAL-UP MODEMS
Modem Standards ADSL 252 ADSL Lite 254 HDSL 255 SDSL 255 VDSL 255 Summary 255 249
248
DIGITAL SUBSCRIBER LINE 251
9.4 9.5
CABLE TV NETWORKS
256
256
Traditional Cable Networks 256 Hybrid Fiber-Coaxial (HFC) Network Bandwidth 257 Sharing 259 CM and CMTS 259 Data Transmission Schemes: DOCSIS
CABLE TV FOR DATA TRANSFER
257
260
9.6 9.7 9.8 9.9
RECOMMENDED READING
Books 261
261
KEY TERMS 261 SUMMARY 262 PRACTICE SET 263
Review Questions Exercises 264 263
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CONTENTS
PART 3
Data Link Layer
265 267
Chapter 10
10.1
Error Detection and Correction
267
INTRODUCTION
Types of Errors 267 Redundancy 269 Detection Versus Correction 269 Forward Error Correction Versus Retransmission Coding 269 Modular Arithmetic 270
269
10.2
BLOCK CODING
271
Error Detection 272 Error Correction 273 Hamming Distance 274 Minimum Hamming Distance
274
10.3 10.4
LINEAR BLOCK CODES CYCLIC CODES 284
277
278
Minimum Distance for Linear Block Codes Some Linear Block Codes 278 Cyclic Redundancy Check 284 Hardware Implementation 287 Polynomials 291 Cyclic Code Analysis 293 Advantages of Cyclic Codes 297 Other Cyclic Codes 297
10.5
CHECKSUM
298
Idea 298 One’s Complement 298 Internet Checksum 299
10.6 10.7 10.8 10.9
RECOMMENDED READING
Books 301 RFCs 301
301
KEY TERMS 301 SUMMARY 302 PRACTICE SET 303
Review Questions Exercises 303 303
Chapter 11
11.1 11.2 11.3 11.4 11.5 FRAMING
Data Link Control
307
307 311
Fixed-Size Framing 308 Variable-Size Framing 308
FLOW AND ERROR CONTROL
Flow Control 311 Error Control 311 PROTOCOLS 311
NOISELESS CHANNELS
Simplest Protocol 312 Stop-and-Wait Protocol 315
312
NOISY CHANNELS
318
Stop-and-Wait Automatic Repeat Request 318 Go-Back-N Automatic Repeat Request 324
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CONTENTS Selective Repeat Automatic Repeat Request Piggybacking 339 332
xv
11.6
HDLC
340
340
Configurations and Transfer Modes Frames 341 Control Field 343
11.7
POINT-TO-POINT PROTOCOL
Framing 348 Transition Phases 349 Multiplexing 350 Multilink PPP 355
346
11.8
RECOMMENDED READING
Books 357
357
11.9 KEY TERMS 357 11.10 SUMMARY 358 11.11 PRACTICE SET 359
Review Questions Exercises 359 359
Chapter 12
12.1
Multiple Access
364
363
RANDOM ACCESS
ALOHA 365 Carrier Sense Multiple Access (CSMA) 370 Carrier Sense Multiple Access with Collision Detection (CSMA/CD) 373 Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) 377
12.2
CONTROLLED ACCESS
Reservation 379 Polling 380 Token Passing 381
379
12.3
CHANNELIZATION
383
Frequency-Division Multiple Access (FDMA) 383 Time-Division Multiple Access (TDMA) 384 Code-Division Multiple Access (CDMA) 385
12.4 12.5 12.6 12.7
RECOMMENDED READING
Books 391
390
KEY TERMS 391 SUMMARY 391 PRACTICE SET 392
Review Questions 392 Exercises 393 Research Activities 394
Chapter 13
13.1 13.2 13.3
Wired LANs: Ethernet
395 397 406
395
IEEE STANDARDS
Data Link Layer 396 Physical Layer 397
STANDARD ETHERNET
MAC Sublayer 398 Physical Layer 402
CHANGES IN THE STANDARD
Bridged Ethernet 406 Switched Ethernet 407 Full-Duplex Ethernet 408
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CONTENTS
13.4 13.5
FAST ETHERNET
MAC Sublayer 409 Physical Layer 410
409 412
GIGABIT ETHERNET
MAC Sublayer 412 Physical Layer 414 Ten-Gigabit Ethernet 416
13.6 13.7 13.8 13.9
RECOMMENDED READING
Books 417
417
KEY TERMS 417 SUMMARY 417 PRACTICE SET 418
Review Questions Exercises 419 418
Chapter 14
14.1 IEEE 802.11
Wireless LANs
421
428
421
Architecture 421 MAC Sublayer 423 Addressing Mechanism Physical Layer 432
14.2
BLUETOOTH
434
Architecture 435 Bluetooth Layers 436 Radio Layer 436 Baseband Layer 437 L2CAP 440 Other Upper Layers 441
14.3 14.4 14.5 14.6
RECOMMENDED READING
Books 442
441
KEY TERMS 442 SUMMARY 442 PRACTICE SET 443
Review Questions Exercises 443 443
Chapter 15
15.1
Connecting LANs, Backbone Networks, and Virtual LANs 445
445
CONNECTING DEVICES
Passive Hubs 446 Repeaters 446 Active Hubs 447 Bridges 447 Two-Layer Switches 454 Routers 455 Three-Layer Switches 455 Gateway 455
15.2
BACKBONE NETWORKS
Bus Backbone 456 Star Backbone 457 Connecting Remote LANs 457
456
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15.3
VIRTUAL LANs 458 Membership 461 Configuration 461 Communication Between Switches IEEE Standard 462 Advantages 463 RECOMMENDED READING
Books 463 Site 463
462
15.4 15.5 15.6 15.7
463
KEY TERMS 463 SUMMARY 464 PRACTICE SET 464
Review Questions Exercises 465 464
Chapter 16
16.1
Wireless WANs: Cellular Telephone and Satellite Networks 467
467
467
CELLULAR TELEPHONY
Frequency-Reuse Principle Transmitting 468 Receiving 469 Roaming 469 First Generation 469 Second Generation 470 Third Generation 477
16.2
SATELLITE NETWORKS
Orbits 479 Footprint 480 Three Categories of Satellites GEO Satellites 481 MEO Satellites 481 LEO Satellites 484
478
480
16.3 16.4 16.5 16.6
RECOMMENDED READING
Books 487
487
KEY TERMS 487 SUMMARY 487 PRACTICE SET 488
Review Questions Exercises 488 488
Chapter 17
17.1
SONET/SDH
491
491
ARCHITECTURE
Signals 491 SONET Devices 492 Connections 493
17.2
SONET LAYERS
494
Path Layer 494 Line Layer 495 Section Layer 495 Photonic Layer 495 Device–Layer Relationships
495
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CONTENTS
17.3
SONET FRAMES
496
496
Frame, Byte, and Bit Transmission STS-1 Frame Format 497 Overhead Summary 501 Encapsulation 501
17.4
STS MULTIPLEXING
Byte Interleaving 504 Concatenated Signal 505 Add/Drop Multiplexer 506
503
17.5
SONET NETWORKS
Linear Networks 507 Ring Networks 509 Mesh Networks 510
507
17.6 17.7
VIRTUAL TRIBUTARIES
Types of VTs Books 513 512
512 513
RECOMMENDED READING
17.8 KEY TERMS 513 17.9 SUMMARY 514 17.10 PRACTICE SET 514
Review Questions Exercises 515 514
Chapter 18
18.1
Virtual-Circuit Networks: Frame Relay and ATM
517
517
FRAME RELAY
Architecture 518 Frame Relay Layers 519 Extended Address 521 FRADs 522 VOFR 522 LMI 522 Congestion Control and Quality of Service
522
18.2
ATM
523
Design Goals 523 Problems 523 Architecture 526 Switching 529 ATM Layers 529 Congestion Control and Quality of Service
535
18.3
ATM LANs
536
ATM LAN Architecture 536 LAN Emulation (LANE) 538 Client/Server Model 539 Mixed Architecture with Client/Server
540
18.4 18.5 18.6 18.7
RECOMMENDED READING
Books 541
540
KEY TERMS 541 SUMMARY 541 PRACTICE SET 543
Review Questions Exercises 543 543
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PART 4
Network Layer
547 549
Chapter 19
19.1
Network Layer: Logical Addressing
549
IPv4 ADDRESSES
Address Space 550 Notations 550 Classful Addressing 552 Classless Addressing 555 Network Address Translation (NAT)
563
19.2 19.3
IPv6 ADDRESSES
Structure 567 Address Space 568
566 572
RECOMMENDED READING
Books 572 Sites 572 RFCs 572
19.4 19.5 19.6
KEY TERMS 572 SUMMARY 573 PRACTICE SET 574
Review Questions 574 Exercises 574 Research Activities 577
Chapter 20
20.1
Network Layer: Internet Protocol
579
579
INTERNETWORKING
Need for Network Layer 579 Internet as a Datagram Network 581 Internet as a Connectionless Network 582
20.2
IPv4
582
Datagram 583 Fragmentation 589 Checksum 594 Options 594
20.3
IPv6
596
Advantages 597 Packet Format 597 Extension Headers 602
20.4
TRANSITION FROM IPv4 TO IPv6
Dual Stack 604 Tunneling 604 Header Translation 605
603
20.5
RECOMMENDED READING
Books 606 Sites 606 RFCs 606
605
20.6 20.7 20.8
KEY TERMS 606 SUMMARY 607 PRACTICE SET 607
Review Questions 607 Exercises 608 Research Activities 609
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CONTENTS
Chapter 21
21.1 21.2
Network Layer: Address Mapping, Error Reporting, and Multicasting 611
611
618
ADDRESS MAPPING ICMP 621
Mapping Logical to Physical Address: ARP 612 Mapping Physical to Logical Address: RARP, BOOTP, and DHCP Types of Messages 621 Message Format 621 Error Reporting 622 Query 625 Debugging Tools 627
21.3
IGMP
630
Group Management 630 IGMP Messages 631 Message Format 631 IGMP Operation 632 Encapsulation 635 Netstat Utility 637
21.4 21.5
ICMPv6
638
638
Error Reporting Query 639 Books 641 Site 641 RFCs 641
RECOMMENDED READING
640
21.6 21.7 21.8
KEY TERMS 641 SUMMARY 642 PRACTICE SET 643
Review Questions 643 Exercises 644 Research Activities 645
Chapter 22
22.1 22.2 DELIVERY
Network Layer: Delivery, Forwarding, and Routing 647
647
647
Direct Versus Indirect Delivery
FORWARDING
648
Forwarding Techniques 648 Forwarding Process 650 Routing Table 655
22.3
UNICAST ROUTING PROTOCOLS
Optimization 658 Intra- and Interdomain Routing Distance Vector Routing 660 Link State Routing 666 Path Vector Routing 674 659
658
22.4
MULTICAST ROUTING PROTOCOLS
Unicast, Multicast, and Broadcast Applications 681 Multicast Routing 682 Routing Protocols 684 678
678
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22.5
RECOMMENDED READING
Books 694 Sites 694 RFCs 694
694
22.6 22.7 22.8
KEY TERMS 694 SUMMARY 695 PRACTICE SET 697
Review Questions 697 Exercises 697 Research Activities 699
PART 5
Transport Layer
701
Chapter 23
23.1
Process-to-Process Delivery: UDP, TCP, and SCTP 703
703
707
PROCESS-TO-PROCESS DELIVERY
Client/Server Paradigm 704 Multiplexing and Demultiplexing 707 Connectionless Versus Connection-Oriented Service Reliable Versus Unreliable 708 Three Protocols 708
23.2
USER DATAGRAM PROTOCOL (UDP)
Well-Known Ports for UDP User Datagram 710 Checksum 711 UDP Operation 713 Use of UDP 715 709
709
23.3
TCP
715
TCP Services 715 TCP Features 719 Segment 721 A TCP Connection 723 Flow Control 728 Error Control 731 Congestion Control 735
23.4
SCTP
736
SCTP Services 736 SCTP Features 738 Packet Format 742 An SCTP Association 743 Flow Control 748 Error Control 751 Congestion Control 753
23.5
RECOMMENDED READING
Books 753 Sites 753 RFCs 753
753
23.6 23.7 23.8
KEY TERMS 754 SUMMARY 754 PRACTICE SET 756
Review Questions 756 Exercises 757 Research Activities 759
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CONTENTS
Chapter 24
24.1 24.2 24.3 24.4 24.5 24.6
Congestion Control and Quality of Service
761
761
DATA TRAFFIC
Traffic Descriptor 761 Traffic Profiles 762
CONGESTION 763
Network Performance 764
CONGESTION CONTROL TWO EXAMPLES 768
765
Open-Loop Congestion Control 766 Closed-Loop Congestion Control 767 Congestion Control in TCP 769 Congestion Control in Frame Relay
773
QUALITY OF SERVICE
Flow Characteristics Flow Classes 776 775
775 776
TECHNIQUES TO IMPROVE QoS
Scheduling 776 Traffic Shaping 777 Resource Reservation 780 Admission Control 780
24.7
INTEGRATED SERVICES
780
Signaling 781 Flow Specification 781 Admission 781 Service Classes 781 RSVP 782 Problems with Integrated Services
784
24.8 24.9
DIFFERENTIATED SERVICES
DS Field 785
785 786
QoS IN SWITCHED NETWORKS
QoS in Frame Relay QoS in ATM 789 Books 791 787
24.10 RECOMMENDED READING 24.11 KEY TERMS 791 24.12 SUMMARY 791 24.13 PRACTICE SET 792
Review Questions Exercises 793 792
790
PART 6
Application Layer
795 797
Chapter 25
25.1 25.2
Domain Name System
NAME SPACE 798 Flat Name Space 798 Hierarchical Name Space 798 DOMAIN NAME SPACE
Label 799 Domain Name Domain 801 799
799
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25.3
DISTRIBUTION OF NAME SPACE
Hierarchy of Name Servers 802 Zone 802 Root Server 803 Primary and Secondary Servers 803
801
25.4
DNS IN THE INTERNET
Generic Domains 804 Country Domains 805 Inverse Domain 805
803
25.5
RESOLUTION
806
Resolver 806 Mapping Names to Addresses 807 Mapping Address to Names 807 Recursive Resolution 808 Iterative Resolution 808 Caching 808
25.6 25.7 25.8 25.9 25.10 25.11
DNS MESSAGES
Header 809 Question Record 811 Resource Record 811
809 811
TYPES OF RECORDS
REGISTRARS 811 DYNAMIC DOMAIN NAME SYSTEM (DDNS) ENCAPSULATION 812 RECOMMENDED READING 812
Books 813 Sites 813 RFCs 813
812
25.12 KEY TERMS 813 25.13 SUMMARY 813 25.14 PRACTICE SET 814
Review Questions Exercises 815 814
Chapter 26
26.1 26.2
TELNET 817
Remote Logging, Electronic Mail, and File Transfer 817
817 824
REMOTE LOGGING ELECTRONIC MAIL
Architecture 824 User Agent 828 Message Transfer Agent: SMTP 834 Message Access Agent: POP and IMAP Web-Based Mail 839
837
26.3 26.4
FILE TRANSFER
840
840
File Transfer Protocol (FTP) Anonymous FTP 844 Books 845 Sites 845 RFCs 845
RECOMMENDED READING
845
26.5 26.6
KEY TERMS 845 SUMMARY 846
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CONTENTS
26.7
PRACTICE SET
847
Review Questions 847 Exercises 848 Research Activities 848
Chapter 27
27.1
WWW and HTTP
851
853
851
ARCHITECTURE
Client (Browser) 852 Server 852 Uniform Resource Locator Cookies 853
27.2
WEB DOCUMENTS
854
Static Documents 855 Dynamic Documents 857 Active Documents 860
27.3
HTTP
861
868
HTTP Transaction 861 Persistent Versus Nonpersistent Connection Proxy Server 868
27.4
RECOMMENDED READING
Books 869 Sites 869 RFCs 869
869
27.5 27.6 27.7
KEY TERMS 869 SUMMARY 870 PRACTICE SET 871
Review Questions Exercises 871 871
Chapter 28
28.1
Network Management: SNMP
873
873
NETWORK MANAGEMENT SYSTEM
Configuration Management 874 Fault Management 875 Performance Management 876 Security Management 876 Accounting Management 877
28.2
SIMPLE NETWORK MANAGEMENT PROTOCOL (SNMP)
Concept 877 Management Components 878 Structure of Management Information 881 Management Information Base (MIB) 886 Lexicographic Ordering 889 SNMP 891 Messages 893 UDP Ports 895 Security 897
877
28.3
RECOMMENDED READING
Books 897 Sites 897 RFCs 897
897
28.4 28.5
KEY TERMS 897 SUMMARY 898
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28.6
PRACTICE SET
Review Questions Exercises 899
899
899
Chapter 29
29.1 29.2 29.3
Multimedia
901
902 903 908
DIGITIZING AUDIO AND VIDEO
Digitizing Audio 902 Digitizing Video 902
AUDIO AND VIDEO COMPRESSION
Audio Compression 903 Video Compression 904
STREAMING STORED AUDIO/VIDEO
First Approach: Using a Web Server 909 Second Approach: Using a Web Server with Metafile 909 Third Approach: Using a Media Server 910 Fourth Approach: Using a Media Server and RTSP 911
29.4 29.5 29.6 29.7
STREAMING LIVE AUDIO/VIDEO 912 REAL-TIME INTERACTIVE AUDIO/VIDEO
Characteristics 912 917
912
RTP RTCP
916 919
RTP Packet Format UDP Port 919
Sender Report 919 Receiver Report 920 Source Description Message 920 Bye Message 920 Application-Specific Message 920 UDP Port 920
29.8 29.9
VOICE OVER IP
SIP 920 H.323 923
920 925
RECOMMENDED READING
Books 925 Sites 925
29.10 KEY TERMS 925 29.11 SUMMARY 926 29.12 PRACTICE SET 927
Review Questions 927 Exercises 927 Research Activities 928
PART 7
Security
929 931
Chapter 30
30.1 30.2
Cryptography
931
INTRODUCTION
Definitions 931 Two Categories 932
SYMMETRIC-KEY CRYPTOGRAPHY
Traditional Ciphers 935 Simple Modern Ciphers 938
935
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CONTENTS Modern Round Ciphers 940 Mode of Operation 945
30.3 30.4 30.5 30.6 30.7
ASYMMETRIC-KEY CRYPTOGRAPHY
RSA 949 Diffie-Hellman Books 956 952
949
RECOMMENDED READING KEY TERMS 956 SUMMARY 957 PRACTICE SET 958
Review Questions 958 Exercises 959 Research Activities 960
956
Chapter 31
31.1
Network Security
961
961
SECURITY SERVICES
Message Confidentiality 962 Message Integrity 962 Message Authentication 962 Message Nonrepudiation 962 Entity Authentication 962
31.2 31.3
MESSAGE CONFIDENTIALITY MESSAGE INTEGRITY 964
962
Confidentiality with Symmetric-Key Cryptography 963 Confidentiality with Asymmetric-Key Cryptography 963 Document and Fingerprint 965 Message and Message Digest 965 Difference 965 Creating and Checking the Digest 966 Hash Function Criteria 966 Hash Algorithms: SHA-1 967
31.4 31.5
MESSAGE AUTHENTICATION
MAC 969
969
DIGITAL SIGNATURE
Comparison 971 Need for Keys 972 Process 973 Services 974 Signature Schemes 976
971
31.6 31.7 31.8
ENTITY AUTHENTICATION
Passwords 976 Challenge-Response 978
976
KEY MANAGEMENT
981 990
Symmetric-Key Distribution 981 Public-Key Distribution 986
RECOMMENDED READING
Books 990
31.9 KEY TERMS 990 31.10 SUMMARY 991 31.11 PRACTICE SET 992
Review Questions 992 Exercises 993 Research Activities 994
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xxvii
Chapter 32
32.1
Security in the Internet: IPSec, SSL/TLS, PGP, VPN, and Firewalls 995
996
IPSecurity (IPSec)
Two Modes 996 Two Security Protocols 998 Security Association 1002 Internet Key Exchange (IKE) 1004 Virtual Private Network 1004
32.2
SSL/TLS
1008
SSL Services 1008 Security Parameters 1009 Sessions and Connections 1011 Four Protocols 1012 Transport Layer Security 1013
32.3
PGP
1014
Security Parameters 1015 Services 1015 A Scenario 1016 PGP Algorithms 1017 Key Rings 1018 PGP Certificates 1019
32.4 32.5 32.6 32.7 32.8
FIREWALLS
1021 1024
Packet-Filter Firewall 1022 Proxy Firewall 1023
RECOMMENDED READING
Books 1024
KEY TERMS 1024 SUMMARY 1025 PRACTICE SET 1026
Review Questions Exercises 1026 1026
Appendix A
A.1 UNICODE
Unicode
1029
1029
Planes 1030 Basic Multilingual Plane (BMP) 1030 Supplementary Multilingual Plane (SMP) 1032 Supplementary Ideographic Plane (SIP) 1032 Supplementary Special Plane (SSP) 1032 Private Use Planes (PUPs) 1032
A.2
ASCII
1032
1036
Some Properties of ASCII
Appendix B
B.1 B.2
Weights 1038
Numbering Systems
1037
1037
BASE 10: DECIMAL BASE 2: BINARY
Weights 1038 Conversion 1038
1038
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CONTENTS
B.3
BASE 16: HEXADECIMAL
Weights 1039 Conversion 1039 A Comparison 1040
1039
B.4 B.5
BASE 256: IP ADDRESSES
Weights 1040 Conversion 1040
1040
OTHER CONVERSIONS
1041
Binary and Hexadecimal 1041 Base 256 and Binary 1042
Appendix C
C.1
Mathematical Review
1043
1043
TRIGONOMETRIC FUNCTIONS
Sine Wave 1043 Cosine Wave 1045 Other Trigonometric Functions 1046 Trigonometric Identities 1046
C.2 C.3
FOURIER ANALYSIS
Fourier Series 1046 Fourier Transform 1048
1046 1050
EXPONENT AND LOGARITHM
Exponential Function 1050 Logarithmic Function 1051
Appendix D Appendix E
8B/6T Code
1055 1059
Telephone History
1059
Before 1984 1059 Between 1984 and 1996 After 1996 1059
Appendix F Appendix G Appendix H Acronyms Glossary References Index 1111 1067 1071 1107
Contact Addresses RFCs 1063 UDP and TCP Ports
1061 1065
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Preface
Data communications and networking may be the fastest growing technologies in our culture today. One of the ramifications of that growth is a dramatic increase in the number of professions where an understanding of these technologies is essential for success— and a proportionate increase in the number and types of students taking courses to learn about them.
Features of the Book
Several features of this text are designed to make it particularly easy for students to understand data communications and networking. Structure We have used the five-layer Internet model as the framework for the text not only because a thorough understanding of the model is essential to understanding most current networking theory but also because it is based on a structure of interdependencies: Each layer builds upon the layer beneath it and supports the layer above it. In the same way, each concept introduced in our text builds upon the concepts examined in the previous sections. The Internet model was chosen because it is a protocol that is fully implemented. This text is designed for students with little or no background in telecommunications or data communications. For this reason, we use a bottom-up approach. With this approach, students learn first about data communications (lower layers) before learning about networking (upper layers). Visual Approach The book presents highly technical subject matter without complex formulas by using a balance of text and figures. More than 700 figures accompanying the text provide a visual and intuitive opportunity for understanding the material. Figures are particularly important in explaining networking concepts, which are based on connections and transmission. Both of these ideas are easy to grasp visually. Highlighted Points We emphasize important concepts in highlighted boxes for quick reference and immediate attention. xxix for67757_fm.fm Page xxx Monday, January 9, 2006 12:10 PM
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PREFACE
Examples and Applications When appropriate, we have selected examples to reflect true-to-life situations. For example, in Chapter 6 we have shown several cases of telecommunications in current telephone networks. Recommended Reading Each chapter includes a list of books and sites that can be used for further reading. Key Terms Each chapter includes a list of key terms for the student. Summary Each chapter ends with a summary of the material covered in that chapter. The summary provides a brief overview of all the important points in the chapter. Practice Set Each chapter includes a practice set designed to reinforce and apply salient concepts. It consists of three parts: review questions, exercises, and research activities (only for appropriate chapters). Review questions are intended to test the student 's first-level understanding of the material presented in the chapter. Exercises require deeper understanding of the material. Research activities are designed to create motivation for further study. Appendixes The appendixes are intended to provide quick reference material or a review of materials needed to understand the concepts discussed in the book. Glossary and Acronyms The book contains an extensive glossary and a list of acronyms.
Changes in the Fourth Edition
The Fourth Edition has major changes from the Third Edition, both in the organization and in the contents. Organization The following lists the changes in the organization of the book: 1. Chapter 6 now contains multiplexing as well as spreading. 2. Chapter 8 is now totally devoted to switching. 3. The contents of Chapter 12 are moved to Chapter 11. 4. Chapter 17 covers SONET technology. 5. Chapter 19 discusses IP addressing. 6. Chapter 20 is devoted to the Internet Protocol. 7. Chapter 21 discusses three protocols: ARP, ICMP, and IGMP. 8. Chapter 28 is new and devoted to network management in the Internet. 9. The previous Chapters 29 to 31 are now Chapters 30 to 32.
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Contents We have revised the contents of many chapters including the following: 1. The contents of Chapters 1 to 5 are revised and augmented. Examples are added to clarify the contents. 2. The contents of Chapter 10 are revised and augmented to include methods of error detection and correction. 3. Chapter 11 is revised to include a full discussion of several control link protocols. 4. Delivery, forwarding, and routing of datagrams are added to Chapter 22. 5. The new transport protocol, SCTP, is added to Chapter 23. 6. The contents of Chapters 30, 31, and 32 are revised and augmented to include additional discussion about security issues and the Internet. 7. New examples are added to clarify the understanding of concepts. End Materials 1. A section is added to the end of each chapter listing additional sources for study. 2. The review questions are changed and updated. 3. The multiple-choice questions are moved to the book site to allow students to self-test their knowledge about the contents of the chapter and receive immediate feedback. 4. Exercises are revised and new ones are added to the appropriate chapters. 5. Some chapters contain research activities. Instructional Materials Instructional materials for both the student and the teacher are revised and augmented. The solutions to exercises contain both the explanation and answer including full colored figures or tables when needed. The Powerpoint presentations are more comprehensive and include text and figures.
Contents
The book is divided into seven parts. The first part is an overview; the last part concerns network security. The middle five parts are designed to represent the five layers of the Internet model. The following summarizes the contents of each part. Part One: Overview The first part gives a general overview of data communications and networking. Chapter 1 covers introductory concepts needed for the rest of the book. Chapter 2 introduces the Internet model. Part Two: Physical Layer The second part is a discussion of the physical layer of the Internet model. Chapters 3 to 6 discuss telecommunication aspects of the physical layer. Chapter 7 introduces the transmission media, which, although not part of the physical layer, is controlled by it. Chapter 8 is devoted to switching, which can be used in several layers. Chapter 9 shows how two public networks, telephone and cable TV, can be used for data transfer.
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PREFACE
Part Three: Data Link Layer The third part is devoted to the discussion of the data link layer of the Internet model. Chapter 10 covers error detection and correction. Chapters 11, 12 discuss issues related to data link control. Chapters 13 through 16 deal with LANs. Chapters 17 and 18 are about WANs. LANs and WANs are examples of networks operating in the first two layers of the Internet model. Part Four: Network Layer The fourth part is devoted to the discussion of the network layer of the Internet model. Chapter 19 covers IP addresses. Chapters 20 and 21 are devoted to the network layer protocols such as IP, ARP, ICMP, and IGMP. Chapter 22 discusses delivery, forwarding, and routing of packets in the Internet. Part Five: Transport Layer The fifth part is devoted to the discussion of the transport layer of the Internet model. Chapter 23 gives an overview of the transport layer and discusses the services and duties of this layer. It also introduces three transport-layer protocols: UDP, TCP, and SCTP. Chapter 24 discusses congestion control and quality of service, two issues related to the transport layer and the previous two layers. Part Six: Application Layer The sixth part is devoted to the discussion of the application layer of the Internet model. Chapter 25 is about DNS, the application program that is used by other application programs to map application layer addresses to network layer addresses. Chapter 26 to 29 discuss some common applications protocols in the Internet. Part Seven: Security The seventh part is a discussion of security. It serves as a prelude to further study in this subject. Chapter 30 briefly discusses cryptography. Chapter 31 introduces security aspects. Chapter 32 shows how different security aspects can be applied to three layers of the Internet model.
Online Learning Center
The McGraw-Hill Online Learning Center contains much additional material. Available at www.mhhe.com/forouzan. As students read through Data Communications and Networking, they can go online to take self-grading quizzes. They can also access lecture materials such as PowerPoint slides, and get additional review from animated figures from the book. Selected solutions are also available over the Web. The solutions to odd-numbered problems are provided to students, and instructors can use a password to access the complete set of solutions. Additionally, McGraw-Hill makes it easy to create a website for your networking course with an exclusive McGraw-Hill product called PageOut. It requires no prior knowledge of HTML, no long hours, and no design skills on your part. Instead, PageOut offers a series of templates. Simply fill them with your course information and
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PREFACE
xxxiii
click on one of 16 designs. The process takes under an hour and leaves you with a professionally designed website. Although PageOut offers “instant” development, the finished website provides powerful features. An interactive course syllabus allows you to post content to coincide with your lectures, so when students visit your PageOut website, your syllabus will direct them to components of Forouzan’s Online Learning Center, or specific material of your own.
How to Use the Book
This book is written for both an academic and a professional audience. The book can be used as a self-study guide for interested professionals. As a textbook, it can be used for a one-semester or one-quarter course. The following are some guidelines.
❏ Parts one to three are strongly recommended. ❏ Parts four to six can be covered if there is no following course in TCP/IP protocol. ❏ Part seven is recommended if there is no following course in network security. Acknowledgments
It is obvious that the development of a book of this scope needs the support of many people. Peer Review The most important contribution to the development of a book such as this comes from peer reviews. We cannot express our gratitude in words to the many reviewers who spent numerous hours reading the manuscript and providing us with helpful comments and ideas. We would especially like to acknowledge the contributions of the following reviewers for the third and fourth editions of this book. Farid Ahmed, Catholic University Kaveh Ashenayi, University of Tulsa Yoris Au, University of Texas, San Antonio Essie Bakhtiar, Clayton College & State University Anthony Barnard, University of Alabama, Brimingham A.T. Burrell, Oklahoma State University Scott Campbell, Miami University Teresa Carrigan, Blackburn College Hwa Chang, Tufts University Edward Chlebus, Illinois Institute of Technology Peter Cooper, Sam Houston State University Richard Coppins, Virginia Commonwealth University Harpal Dhillon, Southwestern Oklahoma State University Hans-Peter Dommel, Santa Clara University M. Barry Dumas, Baruch College, CUNY William Figg, Dakota State University Dale Fox, Quinnipiac University Terrence Fries, Coastal Carolina University Errin Fulp, Wake Forest University
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PREFACE
Sandeep Gupta, Arizona State University George Hamer, South Dakota State University James Henson, California State University, Fresno Tom Hilton, Utah State University Allen Holliday, California State University, Fullerton Seyed Hossein Hosseini, University of Wisconsin, Milwaukee Gerald Isaacs, Carroll College, Waukesha Hrishikesh Joshi, DeVry University E.S. Khosravi, Southern University Bob Kinicki, Worcester Polytechnic University Kevin Kwiat, Hamilton College Ten-Hwang Lai, Ohio State University Chung-Wei Lee, Auburn University Ka-Cheong Leung, Texas Tech University Gertrude Levine, Fairleigh Dickinson University Alvin Sek See Lim, Auburn University Charles Liu, California State University, Los Angeles Wenhang Liu, California State University, Los Angeles Mark Llewellyn, University of Central Florida Sanchita Mal-Sarkar, Cleveland State University Louis Marseille, Harford Community College Kevin McNeill, University of Arizona Arnold C. Meltzer, George Washington University Rayman Meservy, Brigham Young University Prasant Mohapatra, University of California, Davis Hung Z Ngo, SUNY, Buffalo Larry Owens, California State University, Fresno Arnold Patton, Bradley University Dolly Samson, Hawaii Pacific University Joseph Sherif, California State University, Fullerton Robert Simon, George Mason University Ronald J. Srodawa, Oakland University Daniel Tian, California State University, Monterey Bay Richard Tibbs, Radford University Christophe Veltsos, Minnesota State University, Mankato Yang Wang, University of Maryland, College Park Sherali Zeadally, Wayne State University McGraw-Hill Staff Special thanks go to the staff of McGraw-Hill. Alan Apt, our publisher, proved how a proficient publisher can make the impossible possible. Rebecca Olson, the developmental editor, gave us help whenever we needed it. Sheila Frank, our project manager, guided us through the production process with enormous enthusiasm. We also thank David Hash in design, Kara Kudronowicz in production, and Patti Scott, the copy editor.
References: 1061 1065 for67757_fm.fm Page xxix Saturday, January 7, 2006 12:00 AM xxix for67757_fm.fm Page xxx Monday, January 9, 2006 12:10 PM for67757_fm.fm Page xxxi Saturday, January 7, 2006 12:00 AM PREFACE for67757_fm.fm Page xxxii Saturday, January 7, 2006 12:00 AM xxxii for67757_fm.fm Page xxxiii Monday, January 9, 2006 9:14 PM PREFACE for67757_fm.fm Page xxxiv Monday, January 9, 2006 9:14 PM xxxiv
DATA COMMUNICATIONS AND NETWORKING
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McGraw-Hill Forouzan Networking Series
Titles by Behrouz A. Forouzan: Data Communications and Networking TCP/IP Protocol Suite Local Area Networks Business Data Communications
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DATA COMMUNICATIONS AND NETWORKING
Fourth Edition
Behrouz A. Forouzan
DeAnza College
with
Sophia Chung Fegan
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New copyright page to come
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To my wife, Faezeh, with love Behrouz Forouzan
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BRIEF CONTENTS
Preface PART 1
xxix Overview Introduction 1 3 27 55
Chapter 1 Chapter 2 PART 2 Chapter 3 Chapter 4 Chapter 5 Chapter 6 Chapter 7 Chapter 8 Chapter 9 PART 3 Chapter 10 Chapter 11 Chapter 12 Chapter 13 Chapter 14 Chapter 15 Chapter 16 Chapter 17 Chapter 18
Network Models
Physical Layer and Media Data and Signals 57 101 141 Digital Transmission Analog Transmission Transmission Media Switching 213
Bandwidth Utilization: Multiplexing and Spreading 191
161
Using Telephone and Cable Networks for Data Transmission 241 Data Link Layer Data Link Control Multiple Access Wireless LANs 265 267 307 395
Error Detection and Correction 363 421
Wired LANs: Ethernet
Connecting LANs, Backbone Networks, and Virtual LANs 445 Wireless WANs: Cellular Telephone and Satellite Networks 467 SONET/SDH 491 517 vii Virtual-Circuit Networks: Frame Relay and ATM
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BRIEF CONTENTS
PART 4 Chapter 19 Chapter 20 Chapter 21 Chapter 22 PART 5 Chapter 23 Chapter 24 PART 6 Chapter 25 Chapter 26 Chapter 27 Chapter 28 Chapter 29 PART 7 Chapter 30 Chapter 31 Chapter 32 Appendix A Appendix B Appendix C Appendix D Appendix E Appendix F Appendix G Appendix H Acronyms Glossary References Index 1111
Network Layer
547 549 579
Network Layer: Logical Addressing Network Layer: Internet Protocol
Network Layer: Address Mapping, Error Reporting, and Multicasting 611 Network Layer: Delivery, Forwarding, and Routing Transport Layer 701 703 761 647
Process-to-Process Delivery: UDP, TCP, and SCTP Congestion Control and Quality of Service Application Layer 795 797
Domain Name System WWW and HTTP Multimedia Security 901 851
Remote Logging, Electronic Mail, and File Transfer Network Management: SNMP 873
817
929 931 961
Cryptography
Network Security
Security in the Internet: IPSec, SSL/TLS, PGP, VPN, and Firewalls 995 Unicode 1029 1037 1043 Numbering Systems Mathematical Review 8B/6T Code 1055 1059 1061 1065 Telephone History Contact Addresses RFCs 1063 UDP and TCP Ports
1067 1071 1107
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CONTENTS
Preface
xxix Overview 1 3
3
PART 1
Chapter 1
1.1
Introduction
DATA COMMUNICATIONS
Components 4 Data Representation Data Flow 6 5
1.2
NETWORKS
7
Distributed Processing 7 Network Criteria 7 Physical Structures 8 Network Models 13 Categories of Networks 13 Interconnection of Networks: Internetwork
15
1.3 1.4
THE INTERNET
16 19
A Brief History 17 The Internet Today 17
PROTOCOLS AND STANDARDS
Protocols 19 Standards 19 Standards Organizations Internet Standards 21 20
1.5
RECOMMENDED READING
Books 21 Sites 22 RFCs 22
21
1.6 1.7 1.8
KEY TERMS 22 SUMMARY 23 PRACTICE SET 24
Review Questions 24 Exercises 24 Research Activities 25
Chapter 2
2.1
Network Models
27
28
27
LAYERED TASKS
Sender, Receiver, and Carrier Hierarchy 29
ix
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CONTENTS
2.2
THE OSI MODEL
29
Layered Architecture 30 Peer-to-Peer Processes 30 Encapsulation 33
2.3
LAYERS IN THE OSI MODEL
Physical Layer 33 Data Link Layer 34 Network Layer 36 Transport Layer 37 Session Layer 39 Presentation Layer 39 Application Layer 41 Summary of Layers 42
33
2.4
TCP/IP PROTOCOL SUITE
Physical and Data Link Layers Network Layer 43 Transport Layer 44 Application Layer 45
42
43
2.5
ADDRESSING
45
Physical Addresses 46 Logical Addresses 47 Port Addresses 49 Specific Addresses 50
2.6
RECOMMENDED READING
Books 51 Sites 51 RFCs 51
50
2.7 2.8 2.9
KEY TERMS 51 SUMMARY 52 PRACTICE SET 52
Review Questions 52 Exercises 53 Research Activities 54
PART 2
Physical Layer and Media Data and Signals
57
58
55
Chapter 3
3.1
57
ANALOG AND DIGITAL
Analog and Digital Data 57 Analog and Digital Signals 58 Periodic and Nonperiodic Signals
3.2
PERIODIC ANALOG SIGNALS
59
3.3
Sine Wave 59 Phase 63 Wavelength 64 Time and Frequency Domains 65 Composite Signals 66 Bandwidth 69 DIGITAL SIGNALS 71 Bit Rate 73 Bit Length 73 Digital Signal as a Composite Analog Signal Transmission of Digital Signals 74
74
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CONTENTS
xi
3.4
TRANSMISSION IMPAIRMENT
Attenuation 81 Distortion 83 Noise 84
80
3.5
DATA RATE LIMITS
85
Noiseless Channel: Nyquist Bit Rate 86 Noisy Channel: Shannon Capacity 87 Using Both Limits 88
3.6
PERFORMANCE
89
Bandwidth 89 Throughput 90 Latency (Delay) 90 Bandwidth-Delay Product Jitter 94
92
3.7 3.8 3.9 3.10
RECOMMENDED READING
Books 94
94
KEY TERMS 94 SUMMARY 95 PRACTICE SET 96
Review Questions Exercises 96 96
Chapter 4
4.1
Digital Transmission
101
101
DIGITAL-TO-DIGITAL CONVERSION
Line Coding 101 Line Coding Schemes Block Coding 115 Scrambling 118 106
4.2 4.3 4.4 4.5 4.6 4.7
ANALOG-TO-DIGITAL CONVERSION
Pulse Code Modulation (PCM) Delta Modulation (DM) 129 121
120
TRANSMISSION MODES
Parallel Transmission 131 Serial Transmission 132
131 135
RECOMMENDED READING
Books 135
KEY TERMS 135 SUMMARY 136 PRACTICE SET 137
Review Questions Exercises 137 137
Chapter 5
5.1
Analog Transmission
141
141
142
DIGITAL-TO-ANALOG CONVERSION
Aspects of Digital-to-Analog Conversion Amplitude Shift Keying 143 Frequency Shift Keying 146 Phase Shift Keying 148 Quadrature Amplitude Modulation 152
5.2
ANALOG-TO-ANALOG CONVERSION
Amplitude Modulation 153 Frequency Modulation 154 Phase Modulation 155
152
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CONTENTS
5.3 5.4 5.5 5.6
RECOMMENDED READING
Books 156
156
KEY TERMS 157 SUMMARY 157 PRACTICE SET 158
Review Questions 158 Exercises 158
Chapter 6
6.1
Bandwidth Utilization: Multiplexing and Spreading 161
161
MULTIPLEXING
Frequency-Division Multiplexing 162 Wavelength-Division Multiplexing 167 Synchronous Time-Division Multiplexing 169 Statistical Time-Division Multiplexing 179
6.2 6.3 6.4 6.5 6.6
SPREAD SPECTRUM
180
181
Frequency Hopping Spread Spectrum (FHSS) Direct Sequence Spread Spectrum 184
RECOMMENDED READING
Books 185
185
KEY TERMS 185 SUMMARY 186 PRACTICE SET 187
Review Questions 187 Exercises 187
Chapter 7
7.1
Transmission Media
192
191
GUIDED MEDIA
Twisted-Pair Cable 193 Coaxial Cable 195 Fiber-Optic Cable 198
7.2
UNGUIDED MEDIA: WIRELESS
Radio Waves 205 Microwaves 206 Infrared 207
203
7.3 7.4 7.5 7.6
RECOMMENDED READING
Books 208
208
KEY TERMS 208 SUMMARY 209 PRACTICE SET 209
Review Questions Exercises 210 209
Chapter 8
8.1
Switching
213
214
CIRCUIT-SWITCHED NETWORKS
Three Phases 217 Efficiency 217 Delay 217 Circuit-Switched Technology in Telephone Networks
218
8.2
DATAGRAM NETWORKS
Routing Table 220
218
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CONTENTS Efficiency 220 Delay 221 Datagram Networks in the Internet
xiii
221
8.3
VIRTUAL-CIRCUIT NETWORKS
221
Addressing 222 Three Phases 223 Efficiency 226 Delay in Virtual-Circuit Networks 226 Circuit-Switched Technology in WANs 227
8.4 8.5 8.6 8.7 8.8
STRUCTURE OF A SWITCH
Structure of Circuit Switches 227 Structure of Packet Switches 232
227 235
RECOMMENDED READING
Books 235
KEY TERMS 235 SUMMARY 236 PRACTICE SET 236
Review Questions Exercises 237 236
Chapter 9
9.1
Using Telephone and Cable Networks for Data Transmission 241
241
TELEPHONE NETWORK
Major Components 241 LATAs 242 Signaling 244 Services Provided by Telephone Networks
247
9.2 9.3
DIAL-UP MODEMS
Modem Standards ADSL 252 ADSL Lite 254 HDSL 255 SDSL 255 VDSL 255 Summary 255 249
248
DIGITAL SUBSCRIBER LINE 251
9.4 9.5
CABLE TV NETWORKS
256
256
Traditional Cable Networks 256 Hybrid Fiber-Coaxial (HFC) Network Bandwidth 257 Sharing 259 CM and CMTS 259 Data Transmission Schemes: DOCSIS
CABLE TV FOR DATA TRANSFER
257
260
9.6 9.7 9.8 9.9
RECOMMENDED READING
Books 261
261
KEY TERMS 261 SUMMARY 262 PRACTICE SET 263
Review Questions Exercises 264 263
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CONTENTS
PART 3
Data Link Layer
265 267
Chapter 10
10.1
Error Detection and Correction
267
INTRODUCTION
Types of Errors 267 Redundancy 269 Detection Versus Correction 269 Forward Error Correction Versus Retransmission Coding 269 Modular Arithmetic 270
269
10.2
BLOCK CODING
271
Error Detection 272 Error Correction 273 Hamming Distance 274 Minimum Hamming Distance
274
10.3 10.4
LINEAR BLOCK CODES CYCLIC CODES 284
277
278
Minimum Distance for Linear Block Codes Some Linear Block Codes 278 Cyclic Redundancy Check 284 Hardware Implementation 287 Polynomials 291 Cyclic Code Analysis 293 Advantages of Cyclic Codes 297 Other Cyclic Codes 297
10.5
CHECKSUM
298
Idea 298 One’s Complement 298 Internet Checksum 299
10.6 10.7 10.8 10.9
RECOMMENDED READING
Books 301 RFCs 301
301
KEY TERMS 301 SUMMARY 302 PRACTICE SET 303
Review Questions Exercises 303 303
Chapter 11
11.1 11.2 11.3 11.4 11.5 FRAMING
Data Link Control
307
307 311
Fixed-Size Framing 308 Variable-Size Framing 308
FLOW AND ERROR CONTROL
Flow Control 311 Error Control 311 PROTOCOLS 311
NOISELESS CHANNELS
Simplest Protocol 312 Stop-and-Wait Protocol 315
312
NOISY CHANNELS
318
Stop-and-Wait Automatic Repeat Request 318 Go-Back-N Automatic Repeat Request 324
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CONTENTS Selective Repeat Automatic Repeat Request Piggybacking 339 332
xv
11.6
HDLC
340
340
Configurations and Transfer Modes Frames 341 Control Field 343
11.7
POINT-TO-POINT PROTOCOL
Framing 348 Transition Phases 349 Multiplexing 350 Multilink PPP 355
346
11.8
RECOMMENDED READING
Books 357
357
11.9 KEY TERMS 357 11.10 SUMMARY 358 11.11 PRACTICE SET 359
Review Questions Exercises 359 359
Chapter 12
12.1
Multiple Access
364
363
RANDOM ACCESS
ALOHA 365 Carrier Sense Multiple Access (CSMA) 370 Carrier Sense Multiple Access with Collision Detection (CSMA/CD) 373 Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) 377
12.2
CONTROLLED ACCESS
Reservation 379 Polling 380 Token Passing 381
379
12.3
CHANNELIZATION
383
Frequency-Division Multiple Access (FDMA) 383 Time-Division Multiple Access (TDMA) 384 Code-Division Multiple Access (CDMA) 385
12.4 12.5 12.6 12.7
RECOMMENDED READING
Books 391
390
KEY TERMS 391 SUMMARY 391 PRACTICE SET 392
Review Questions 392 Exercises 393 Research Activities 394
Chapter 13
13.1 13.2 13.3
Wired LANs: Ethernet
395 397 406
395
IEEE STANDARDS
Data Link Layer 396 Physical Layer 397
STANDARD ETHERNET
MAC Sublayer 398 Physical Layer 402
CHANGES IN THE STANDARD
Bridged Ethernet 406 Switched Ethernet 407 Full-Duplex Ethernet 408
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CONTENTS
13.4 13.5
FAST ETHERNET
MAC Sublayer 409 Physical Layer 410
409 412
GIGABIT ETHERNET
MAC Sublayer 412 Physical Layer 414 Ten-Gigabit Ethernet 416
13.6 13.7 13.8 13.9
RECOMMENDED READING
Books 417
417
KEY TERMS 417 SUMMARY 417 PRACTICE SET 418
Review Questions Exercises 419 418
Chapter 14
14.1 IEEE 802.11
Wireless LANs
421
428
421
Architecture 421 MAC Sublayer 423 Addressing Mechanism Physical Layer 432
14.2
BLUETOOTH
434
Architecture 435 Bluetooth Layers 436 Radio Layer 436 Baseband Layer 437 L2CAP 440 Other Upper Layers 441
14.3 14.4 14.5 14.6
RECOMMENDED READING
Books 442
441
KEY TERMS 442 SUMMARY 442 PRACTICE SET 443
Review Questions Exercises 443 443
Chapter 15
15.1
Connecting LANs, Backbone Networks, and Virtual LANs 445
445
CONNECTING DEVICES
Passive Hubs 446 Repeaters 446 Active Hubs 447 Bridges 447 Two-Layer Switches 454 Routers 455 Three-Layer Switches 455 Gateway 455
15.2
BACKBONE NETWORKS
Bus Backbone 456 Star Backbone 457 Connecting Remote LANs 457
456
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15.3
VIRTUAL LANs 458 Membership 461 Configuration 461 Communication Between Switches IEEE Standard 462 Advantages 463 RECOMMENDED READING
Books 463 Site 463
462
15.4 15.5 15.6 15.7
463
KEY TERMS 463 SUMMARY 464 PRACTICE SET 464
Review Questions Exercises 465 464
Chapter 16
16.1
Wireless WANs: Cellular Telephone and Satellite Networks 467
467
467
CELLULAR TELEPHONY
Frequency-Reuse Principle Transmitting 468 Receiving 469 Roaming 469 First Generation 469 Second Generation 470 Third Generation 477
16.2
SATELLITE NETWORKS
Orbits 479 Footprint 480 Three Categories of Satellites GEO Satellites 481 MEO Satellites 481 LEO Satellites 484
478
480
16.3 16.4 16.5 16.6
RECOMMENDED READING
Books 487
487
KEY TERMS 487 SUMMARY 487 PRACTICE SET 488
Review Questions Exercises 488 488
Chapter 17
17.1
SONET/SDH
491
491
ARCHITECTURE
Signals 491 SONET Devices 492 Connections 493
17.2
SONET LAYERS
494
Path Layer 494 Line Layer 495 Section Layer 495 Photonic Layer 495 Device–Layer Relationships
495
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CONTENTS
17.3
SONET FRAMES
496
496
Frame, Byte, and Bit Transmission STS-1 Frame Format 497 Overhead Summary 501 Encapsulation 501
17.4
STS MULTIPLEXING
Byte Interleaving 504 Concatenated Signal 505 Add/Drop Multiplexer 506
503
17.5
SONET NETWORKS
Linear Networks 507 Ring Networks 509 Mesh Networks 510
507
17.6 17.7
VIRTUAL TRIBUTARIES
Types of VTs Books 513 512
512 513
RECOMMENDED READING
17.8 KEY TERMS 513 17.9 SUMMARY 514 17.10 PRACTICE SET 514
Review Questions Exercises 515 514
Chapter 18
18.1
Virtual-Circuit Networks: Frame Relay and ATM
517
517
FRAME RELAY
Architecture 518 Frame Relay Layers 519 Extended Address 521 FRADs 522 VOFR 522 LMI 522 Congestion Control and Quality of Service
522
18.2
ATM
523
Design Goals 523 Problems 523 Architecture 526 Switching 529 ATM Layers 529 Congestion Control and Quality of Service
535
18.3
ATM LANs
536
ATM LAN Architecture 536 LAN Emulation (LANE) 538 Client/Server Model 539 Mixed Architecture with Client/Server
540
18.4 18.5 18.6 18.7
RECOMMENDED READING
Books 541
540
KEY TERMS 541 SUMMARY 541 PRACTICE SET 543
Review Questions Exercises 543 543
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xix
PART 4
Network Layer
547 549
Chapter 19
19.1
Network Layer: Logical Addressing
549
IPv4 ADDRESSES
Address Space 550 Notations 550 Classful Addressing 552 Classless Addressing 555 Network Address Translation (NAT)
563
19.2 19.3
IPv6 ADDRESSES
Structure 567 Address Space 568
566 572
RECOMMENDED READING
Books 572 Sites 572 RFCs 572
19.4 19.5 19.6
KEY TERMS 572 SUMMARY 573 PRACTICE SET 574
Review Questions 574 Exercises 574 Research Activities 577
Chapter 20
20.1
Network Layer: Internet Protocol
579
579
INTERNETWORKING
Need for Network Layer 579 Internet as a Datagram Network 581 Internet as a Connectionless Network 582
20.2
IPv4
582
Datagram 583 Fragmentation 589 Checksum 594 Options 594
20.3
IPv6
596
Advantages 597 Packet Format 597 Extension Headers 602
20.4
TRANSITION FROM IPv4 TO IPv6
Dual Stack 604 Tunneling 604 Header Translation 605
603
20.5
RECOMMENDED READING
Books 606 Sites 606 RFCs 606
605
20.6 20.7 20.8
KEY TERMS 606 SUMMARY 607 PRACTICE SET 607
Review Questions 607 Exercises 608 Research Activities 609
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CONTENTS
Chapter 21
21.1 21.2
Network Layer: Address Mapping, Error Reporting, and Multicasting 611
611
618
ADDRESS MAPPING ICMP 621
Mapping Logical to Physical Address: ARP 612 Mapping Physical to Logical Address: RARP, BOOTP, and DHCP Types of Messages 621 Message Format 621 Error Reporting 622 Query 625 Debugging Tools 627
21.3
IGMP
630
Group Management 630 IGMP Messages 631 Message Format 631 IGMP Operation 632 Encapsulation 635 Netstat Utility 637
21.4 21.5
ICMPv6
638
638
Error Reporting Query 639 Books 641 Site 641 RFCs 641
RECOMMENDED READING
640
21.6 21.7 21.8
KEY TERMS 641 SUMMARY 642 PRACTICE SET 643
Review Questions 643 Exercises 644 Research Activities 645
Chapter 22
22.1 22.2 DELIVERY
Network Layer: Delivery, Forwarding, and Routing 647
647
647
Direct Versus Indirect Delivery
FORWARDING
648
Forwarding Techniques 648 Forwarding Process 650 Routing Table 655
22.3
UNICAST ROUTING PROTOCOLS
Optimization 658 Intra- and Interdomain Routing Distance Vector Routing 660 Link State Routing 666 Path Vector Routing 674 659
658
22.4
MULTICAST ROUTING PROTOCOLS
Unicast, Multicast, and Broadcast Applications 681 Multicast Routing 682 Routing Protocols 684 678
678
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22.5
RECOMMENDED READING
Books 694 Sites 694 RFCs 694
694
22.6 22.7 22.8
KEY TERMS 694 SUMMARY 695 PRACTICE SET 697
Review Questions 697 Exercises 697 Research Activities 699
PART 5
Transport Layer
701
Chapter 23
23.1
Process-to-Process Delivery: UDP, TCP, and SCTP 703
703
707
PROCESS-TO-PROCESS DELIVERY
Client/Server Paradigm 704 Multiplexing and Demultiplexing 707 Connectionless Versus Connection-Oriented Service Reliable Versus Unreliable 708 Three Protocols 708
23.2
USER DATAGRAM PROTOCOL (UDP)
Well-Known Ports for UDP User Datagram 710 Checksum 711 UDP Operation 713 Use of UDP 715 709
709
23.3
TCP
715
TCP Services 715 TCP Features 719 Segment 721 A TCP Connection 723 Flow Control 728 Error Control 731 Congestion Control 735
23.4
SCTP
736
SCTP Services 736 SCTP Features 738 Packet Format 742 An SCTP Association 743 Flow Control 748 Error Control 751 Congestion Control 753
23.5
RECOMMENDED READING
Books 753 Sites 753 RFCs 753
753
23.6 23.7 23.8
KEY TERMS 754 SUMMARY 754 PRACTICE SET 756
Review Questions 756 Exercises 757 Research Activities 759
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CONTENTS
Chapter 24
24.1 24.2 24.3 24.4 24.5 24.6
Congestion Control and Quality of Service
761
761
DATA TRAFFIC
Traffic Descriptor 761 Traffic Profiles 762
CONGESTION 763
Network Performance 764
CONGESTION CONTROL TWO EXAMPLES 768
765
Open-Loop Congestion Control 766 Closed-Loop Congestion Control 767 Congestion Control in TCP 769 Congestion Control in Frame Relay
773
QUALITY OF SERVICE
Flow Characteristics Flow Classes 776 775
775 776
TECHNIQUES TO IMPROVE QoS
Scheduling 776 Traffic Shaping 777 Resource Reservation 780 Admission Control 780
24.7
INTEGRATED SERVICES
780
Signaling 781 Flow Specification 781 Admission 781 Service Classes 781 RSVP 782 Problems with Integrated Services
784
24.8 24.9
DIFFERENTIATED SERVICES
DS Field 785
785 786
QoS IN SWITCHED NETWORKS
QoS in Frame Relay QoS in ATM 789 Books 791 787
24.10 RECOMMENDED READING 24.11 KEY TERMS 791 24.12 SUMMARY 791 24.13 PRACTICE SET 792
Review Questions Exercises 793 792
790
PART 6
Application Layer
795 797
Chapter 25
25.1 25.2
Domain Name System
NAME SPACE 798 Flat Name Space 798 Hierarchical Name Space 798 DOMAIN NAME SPACE
Label 799 Domain Name Domain 801 799
799
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CONTENTS
xxiii
25.3
DISTRIBUTION OF NAME SPACE
Hierarchy of Name Servers 802 Zone 802 Root Server 803 Primary and Secondary Servers 803
801
25.4
DNS IN THE INTERNET
Generic Domains 804 Country Domains 805 Inverse Domain 805
803
25.5
RESOLUTION
806
Resolver 806 Mapping Names to Addresses 807 Mapping Address to Names 807 Recursive Resolution 808 Iterative Resolution 808 Caching 808
25.6 25.7 25.8 25.9 25.10 25.11
DNS MESSAGES
Header 809 Question Record 811 Resource Record 811
809 811
TYPES OF RECORDS
REGISTRARS 811 DYNAMIC DOMAIN NAME SYSTEM (DDNS) ENCAPSULATION 812 RECOMMENDED READING 812
Books 813 Sites 813 RFCs 813
812
25.12 KEY TERMS 813 25.13 SUMMARY 813 25.14 PRACTICE SET 814
Review Questions Exercises 815 814
Chapter 26
26.1 26.2
TELNET 817
Remote Logging, Electronic Mail, and File Transfer 817
817 824
REMOTE LOGGING ELECTRONIC MAIL
Architecture 824 User Agent 828 Message Transfer Agent: SMTP 834 Message Access Agent: POP and IMAP Web-Based Mail 839
837
26.3 26.4
FILE TRANSFER
840
840
File Transfer Protocol (FTP) Anonymous FTP 844 Books 845 Sites 845 RFCs 845
RECOMMENDED READING
845
26.5 26.6
KEY TERMS 845 SUMMARY 846
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CONTENTS
26.7
PRACTICE SET
847
Review Questions 847 Exercises 848 Research Activities 848
Chapter 27
27.1
WWW and HTTP
851
853
851
ARCHITECTURE
Client (Browser) 852 Server 852 Uniform Resource Locator Cookies 853
27.2
WEB DOCUMENTS
854
Static Documents 855 Dynamic Documents 857 Active Documents 860
27.3
HTTP
861
868
HTTP Transaction 861 Persistent Versus Nonpersistent Connection Proxy Server 868
27.4
RECOMMENDED READING
Books 869 Sites 869 RFCs 869
869
27.5 27.6 27.7
KEY TERMS 869 SUMMARY 870 PRACTICE SET 871
Review Questions Exercises 871 871
Chapter 28
28.1
Network Management: SNMP
873
873
NETWORK MANAGEMENT SYSTEM
Configuration Management 874 Fault Management 875 Performance Management 876 Security Management 876 Accounting Management 877
28.2
SIMPLE NETWORK MANAGEMENT PROTOCOL (SNMP)
Concept 877 Management Components 878 Structure of Management Information 881 Management Information Base (MIB) 886 Lexicographic Ordering 889 SNMP 891 Messages 893 UDP Ports 895 Security 897
877
28.3
RECOMMENDED READING
Books 897 Sites 897 RFCs 897
897
28.4 28.5
KEY TERMS 897 SUMMARY 898
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28.6
PRACTICE SET
Review Questions Exercises 899
899
899
Chapter 29
29.1 29.2 29.3
Multimedia
901
902 903 908
DIGITIZING AUDIO AND VIDEO
Digitizing Audio 902 Digitizing Video 902
AUDIO AND VIDEO COMPRESSION
Audio Compression 903 Video Compression 904
STREAMING STORED AUDIO/VIDEO
First Approach: Using a Web Server 909 Second Approach: Using a Web Server with Metafile 909 Third Approach: Using a Media Server 910 Fourth Approach: Using a Media Server and RTSP 911
29.4 29.5 29.6 29.7
STREAMING LIVE AUDIO/VIDEO 912 REAL-TIME INTERACTIVE AUDIO/VIDEO
Characteristics 912 917
912
RTP RTCP
916 919
RTP Packet Format UDP Port 919
Sender Report 919 Receiver Report 920 Source Description Message 920 Bye Message 920 Application-Specific Message 920 UDP Port 920
29.8 29.9
VOICE OVER IP
SIP 920 H.323 923
920 925
RECOMMENDED READING
Books 925 Sites 925
29.10 KEY TERMS 925 29.11 SUMMARY 926 29.12 PRACTICE SET 927
Review Questions 927 Exercises 927 Research Activities 928
PART 7
Security
929 931
Chapter 30
30.1 30.2
Cryptography
931
INTRODUCTION
Definitions 931 Two Categories 932
SYMMETRIC-KEY CRYPTOGRAPHY
Traditional Ciphers 935 Simple Modern Ciphers 938
935
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xxvi
CONTENTS Modern Round Ciphers 940 Mode of Operation 945
30.3 30.4 30.5 30.6 30.7
ASYMMETRIC-KEY CRYPTOGRAPHY
RSA 949 Diffie-Hellman Books 956 952
949
RECOMMENDED READING KEY TERMS 956 SUMMARY 957 PRACTICE SET 958
Review Questions 958 Exercises 959 Research Activities 960
956
Chapter 31
31.1
Network Security
961
961
SECURITY SERVICES
Message Confidentiality 962 Message Integrity 962 Message Authentication 962 Message Nonrepudiation 962 Entity Authentication 962
31.2 31.3
MESSAGE CONFIDENTIALITY MESSAGE INTEGRITY 964
962
Confidentiality with Symmetric-Key Cryptography 963 Confidentiality with Asymmetric-Key Cryptography 963 Document and Fingerprint 965 Message and Message Digest 965 Difference 965 Creating and Checking the Digest 966 Hash Function Criteria 966 Hash Algorithms: SHA-1 967
31.4 31.5
MESSAGE AUTHENTICATION
MAC 969
969
DIGITAL SIGNATURE
Comparison 971 Need for Keys 972 Process 973 Services 974 Signature Schemes 976
971
31.6 31.7 31.8
ENTITY AUTHENTICATION
Passwords 976 Challenge-Response 978
976
KEY MANAGEMENT
981 990
Symmetric-Key Distribution 981 Public-Key Distribution 986
RECOMMENDED READING
Books 990
31.9 KEY TERMS 990 31.10 SUMMARY 991 31.11 PRACTICE SET 992
Review Questions 992 Exercises 993 Research Activities 994
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xxvii
Chapter 32
32.1
Security in the Internet: IPSec, SSL/TLS, PGP, VPN, and Firewalls 995
996
IPSecurity (IPSec)
Two Modes 996 Two Security Protocols 998 Security Association 1002 Internet Key Exchange (IKE) 1004 Virtual Private Network 1004
32.2
SSL/TLS
1008
SSL Services 1008 Security Parameters 1009 Sessions and Connections 1011 Four Protocols 1012 Transport Layer Security 1013
32.3
PGP
1014
Security Parameters 1015 Services 1015 A Scenario 1016 PGP Algorithms 1017 Key Rings 1018 PGP Certificates 1019
32.4 32.5 32.6 32.7 32.8
FIREWALLS
1021 1024
Packet-Filter Firewall 1022 Proxy Firewall 1023
RECOMMENDED READING
Books 1024
KEY TERMS 1024 SUMMARY 1025 PRACTICE SET 1026
Review Questions Exercises 1026 1026
Appendix A
A.1 UNICODE
Unicode
1029
1029
Planes 1030 Basic Multilingual Plane (BMP) 1030 Supplementary Multilingual Plane (SMP) 1032 Supplementary Ideographic Plane (SIP) 1032 Supplementary Special Plane (SSP) 1032 Private Use Planes (PUPs) 1032
A.2
ASCII
1032
1036
Some Properties of ASCII
Appendix B
B.1 B.2
Weights 1038
Numbering Systems
1037
1037
BASE 10: DECIMAL BASE 2: BINARY
Weights 1038 Conversion 1038
1038
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CONTENTS
B.3
BASE 16: HEXADECIMAL
Weights 1039 Conversion 1039 A Comparison 1040
1039
B.4 B.5
BASE 256: IP ADDRESSES
Weights 1040 Conversion 1040
1040
OTHER CONVERSIONS
1041
Binary and Hexadecimal 1041 Base 256 and Binary 1042
Appendix C
C.1
Mathematical Review
1043
1043
TRIGONOMETRIC FUNCTIONS
Sine Wave 1043 Cosine Wave 1045 Other Trigonometric Functions 1046 Trigonometric Identities 1046
C.2 C.3
FOURIER ANALYSIS
Fourier Series 1046 Fourier Transform 1048
1046 1050
EXPONENT AND LOGARITHM
Exponential Function 1050 Logarithmic Function 1051
Appendix D Appendix E
8B/6T Code
1055 1059
Telephone History
1059
Before 1984 1059 Between 1984 and 1996 After 1996 1059
Appendix F Appendix G Appendix H Acronyms Glossary References Index 1111 1067 1071 1107
Contact Addresses RFCs 1063 UDP and TCP Ports
1061 1065
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Preface
Data communications and networking may be the fastest growing technologies in our culture today. One of the ramifications of that growth is a dramatic increase in the number of professions where an understanding of these technologies is essential for success— and a proportionate increase in the number and types of students taking courses to learn about them.
Features of the Book
Several features of this text are designed to make it particularly easy for students to understand data communications and networking. Structure We have used the five-layer Internet model as the framework for the text not only because a thorough understanding of the model is essential to understanding most current networking theory but also because it is based on a structure of interdependencies: Each layer builds upon the layer beneath it and supports the layer above it. In the same way, each concept introduced in our text builds upon the concepts examined in the previous sections. The Internet model was chosen because it is a protocol that is fully implemented. This text is designed for students with little or no background in telecommunications or data communications. For this reason, we use a bottom-up approach. With this approach, students learn first about data communications (lower layers) before learning about networking (upper layers). Visual Approach The book presents highly technical subject matter without complex formulas by using a balance of text and figures. More than 700 figures accompanying the text provide a visual and intuitive opportunity for understanding the material. Figures are particularly important in explaining networking concepts, which are based on connections and transmission. Both of these ideas are easy to grasp visually. Highlighted Points We emphasize important concepts in highlighted boxes for quick reference and immediate attention. xxix for67757_fm.fm Page xxx Monday, January 9, 2006 12:10 PM
xxx
PREFACE
Examples and Applications When appropriate, we have selected examples to reflect true-to-life situations. For example, in Chapter 6 we have shown several cases of telecommunications in current telephone networks. Recommended Reading Each chapter includes a list of books and sites that can be used for further reading. Key Terms Each chapter includes a list of key terms for the student. Summary Each chapter ends with a summary of the material covered in that chapter. The summary provides a brief overview of all the important points in the chapter. Practice Set Each chapter includes a practice set designed to reinforce and apply salient concepts. It consists of three parts: review questions, exercises, and research activities (only for appropriate chapters). Review questions are intended to test the student 's first-level understanding of the material presented in the chapter. Exercises require deeper understanding of the material. Research activities are designed to create motivation for further study. Appendixes The appendixes are intended to provide quick reference material or a review of materials needed to understand the concepts discussed in the book. Glossary and Acronyms The book contains an extensive glossary and a list of acronyms.
Changes in the Fourth Edition
The Fourth Edition has major changes from the Third Edition, both in the organization and in the contents. Organization The following lists the changes in the organization of the book: 1. Chapter 6 now contains multiplexing as well as spreading. 2. Chapter 8 is now totally devoted to switching. 3. The contents of Chapter 12 are moved to Chapter 11. 4. Chapter 17 covers SONET technology. 5. Chapter 19 discusses IP addressing. 6. Chapter 20 is devoted to the Internet Protocol. 7. Chapter 21 discusses three protocols: ARP, ICMP, and IGMP. 8. Chapter 28 is new and devoted to network management in the Internet. 9. The previous Chapters 29 to 31 are now Chapters 30 to 32.
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PREFACE
xxxi
Contents We have revised the contents of many chapters including the following: 1. The contents of Chapters 1 to 5 are revised and augmented. Examples are added to clarify the contents. 2. The contents of Chapter 10 are revised and augmented to include methods of error detection and correction. 3. Chapter 11 is revised to include a full discussion of several control link protocols. 4. Delivery, forwarding, and routing of datagrams are added to Chapter 22. 5. The new transport protocol, SCTP, is added to Chapter 23. 6. The contents of Chapters 30, 31, and 32 are revised and augmented to include additional discussion about security issues and the Internet. 7. New examples are added to clarify the understanding of concepts. End Materials 1. A section is added to the end of each chapter listing additional sources for study. 2. The review questions are changed and updated. 3. The multiple-choice questions are moved to the book site to allow students to self-test their knowledge about the contents of the chapter and receive immediate feedback. 4. Exercises are revised and new ones are added to the appropriate chapters. 5. Some chapters contain research activities. Instructional Materials Instructional materials for both the student and the teacher are revised and augmented. The solutions to exercises contain both the explanation and answer including full colored figures or tables when needed. The Powerpoint presentations are more comprehensive and include text and figures.
Contents
The book is divided into seven parts. The first part is an overview; the last part concerns network security. The middle five parts are designed to represent the five layers of the Internet model. The following summarizes the contents of each part. Part One: Overview The first part gives a general overview of data communications and networking. Chapter 1 covers introductory concepts needed for the rest of the book. Chapter 2 introduces the Internet model. Part Two: Physical Layer The second part is a discussion of the physical layer of the Internet model. Chapters 3 to 6 discuss telecommunication aspects of the physical layer. Chapter 7 introduces the transmission media, which, although not part of the physical layer, is controlled by it. Chapter 8 is devoted to switching, which can be used in several layers. Chapter 9 shows how two public networks, telephone and cable TV, can be used for data transfer.
for67757_fm.fm Page xxxii Saturday, January 7, 2006 12:00 AM
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PREFACE
Part Three: Data Link Layer The third part is devoted to the discussion of the data link layer of the Internet model. Chapter 10 covers error detection and correction. Chapters 11, 12 discuss issues related to data link control. Chapters 13 through 16 deal with LANs. Chapters 17 and 18 are about WANs. LANs and WANs are examples of networks operating in the first two layers of the Internet model. Part Four: Network Layer The fourth part is devoted to the discussion of the network layer of the Internet model. Chapter 19 covers IP addresses. Chapters 20 and 21 are devoted to the network layer protocols such as IP, ARP, ICMP, and IGMP. Chapter 22 discusses delivery, forwarding, and routing of packets in the Internet. Part Five: Transport Layer The fifth part is devoted to the discussion of the transport layer of the Internet model. Chapter 23 gives an overview of the transport layer and discusses the services and duties of this layer. It also introduces three transport-layer protocols: UDP, TCP, and SCTP. Chapter 24 discusses congestion control and quality of service, two issues related to the transport layer and the previous two layers. Part Six: Application Layer The sixth part is devoted to the discussion of the application layer of the Internet model. Chapter 25 is about DNS, the application program that is used by other application programs to map application layer addresses to network layer addresses. Chapter 26 to 29 discuss some common applications protocols in the Internet. Part Seven: Security The seventh part is a discussion of security. It serves as a prelude to further study in this subject. Chapter 30 briefly discusses cryptography. Chapter 31 introduces security aspects. Chapter 32 shows how different security aspects can be applied to three layers of the Internet model.
Online Learning Center
The McGraw-Hill Online Learning Center contains much additional material. Available at www.mhhe.com/forouzan. As students read through Data Communications and Networking, they can go online to take self-grading quizzes. They can also access lecture materials such as PowerPoint slides, and get additional review from animated figures from the book. Selected solutions are also available over the Web. The solutions to odd-numbered problems are provided to students, and instructors can use a password to access the complete set of solutions. Additionally, McGraw-Hill makes it easy to create a website for your networking course with an exclusive McGraw-Hill product called PageOut. It requires no prior knowledge of HTML, no long hours, and no design skills on your part. Instead, PageOut offers a series of templates. Simply fill them with your course information and
for67757_fm.fm Page xxxiii Monday, January 9, 2006 9:14 PM
PREFACE
xxxiii
click on one of 16 designs. The process takes under an hour and leaves you with a professionally designed website. Although PageOut offers “instant” development, the finished website provides powerful features. An interactive course syllabus allows you to post content to coincide with your lectures, so when students visit your PageOut website, your syllabus will direct them to components of Forouzan’s Online Learning Center, or specific material of your own.
How to Use the Book
This book is written for both an academic and a professional audience. The book can be used as a self-study guide for interested professionals. As a textbook, it can be used for a one-semester or one-quarter course. The following are some guidelines.
❏ Parts one to three are strongly recommended. ❏ Parts four to six can be covered if there is no following course in TCP/IP protocol. ❏ Part seven is recommended if there is no following course in network security. Acknowledgments
It is obvious that the development of a book of this scope needs the support of many people. Peer Review The most important contribution to the development of a book such as this comes from peer reviews. We cannot express our gratitude in words to the many reviewers who spent numerous hours reading the manuscript and providing us with helpful comments and ideas. We would especially like to acknowledge the contributions of the following reviewers for the third and fourth editions of this book. Farid Ahmed, Catholic University Kaveh Ashenayi, University of Tulsa Yoris Au, University of Texas, San Antonio Essie Bakhtiar, Clayton College & State University Anthony Barnard, University of Alabama, Brimingham A.T. Burrell, Oklahoma State University Scott Campbell, Miami University Teresa Carrigan, Blackburn College Hwa Chang, Tufts University Edward Chlebus, Illinois Institute of Technology Peter Cooper, Sam Houston State University Richard Coppins, Virginia Commonwealth University Harpal Dhillon, Southwestern Oklahoma State University Hans-Peter Dommel, Santa Clara University M. Barry Dumas, Baruch College, CUNY William Figg, Dakota State University Dale Fox, Quinnipiac University Terrence Fries, Coastal Carolina University Errin Fulp, Wake Forest University
for67757_fm.fm Page xxxiv Monday, January 9, 2006 9:14 PM
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PREFACE
Sandeep Gupta, Arizona State University George Hamer, South Dakota State University James Henson, California State University, Fresno Tom Hilton, Utah State University Allen Holliday, California State University, Fullerton Seyed Hossein Hosseini, University of Wisconsin, Milwaukee Gerald Isaacs, Carroll College, Waukesha Hrishikesh Joshi, DeVry University E.S. Khosravi, Southern University Bob Kinicki, Worcester Polytechnic University Kevin Kwiat, Hamilton College Ten-Hwang Lai, Ohio State University Chung-Wei Lee, Auburn University Ka-Cheong Leung, Texas Tech University Gertrude Levine, Fairleigh Dickinson University Alvin Sek See Lim, Auburn University Charles Liu, California State University, Los Angeles Wenhang Liu, California State University, Los Angeles Mark Llewellyn, University of Central Florida Sanchita Mal-Sarkar, Cleveland State University Louis Marseille, Harford Community College Kevin McNeill, University of Arizona Arnold C. Meltzer, George Washington University Rayman Meservy, Brigham Young University Prasant Mohapatra, University of California, Davis Hung Z Ngo, SUNY, Buffalo Larry Owens, California State University, Fresno Arnold Patton, Bradley University Dolly Samson, Hawaii Pacific University Joseph Sherif, California State University, Fullerton Robert Simon, George Mason University Ronald J. Srodawa, Oakland University Daniel Tian, California State University, Monterey Bay Richard Tibbs, Radford University Christophe Veltsos, Minnesota State University, Mankato Yang Wang, University of Maryland, College Park Sherali Zeadally, Wayne State University McGraw-Hill Staff Special thanks go to the staff of McGraw-Hill. Alan Apt, our publisher, proved how a proficient publisher can make the impossible possible. Rebecca Olson, the developmental editor, gave us help whenever we needed it. Sheila Frank, our project manager, guided us through the production process with enormous enthusiasm. We also thank David Hash in design, Kara Kudronowicz in production, and Patti Scott, the copy editor.
References: 1061 1065 for67757_fm.fm Page xxix Saturday, January 7, 2006 12:00 AM xxix for67757_fm.fm Page xxx Monday, January 9, 2006 12:10 PM for67757_fm.fm Page xxxi Saturday, January 7, 2006 12:00 AM PREFACE for67757_fm.fm Page xxxii Saturday, January 7, 2006 12:00 AM xxxii for67757_fm.fm Page xxxiii Monday, January 9, 2006 9:14 PM PREFACE for67757_fm.fm Page xxxiv Monday, January 9, 2006 9:14 PM xxxiv
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Interracial relationships or Miscegenation is a mixture of races; especially in marriage, cohabitation, or sexual relations between a white person and someone of another race (Webster-Merriam). For people of the Millennial generation (those born between 1977 and 2000) interracial dating is not something that is looked down upon nor it is something that is a major concern. But that was not always the case for the Baby Boomer generation (those born between 1946 and 1964). Baby Boomers grew up in an era where interracial relationships were still illegal. It wasn’t until 1967 that the U.S Supreme court ruled laws against miscegenation unconstitutional (Schripper). For someone born in the 1980’s like myself, I find it very difficult to image the possibility of going to jail simply for dating someone with different colored skin. The idea of interracial dating being that taboo and illegal is hard to imagine for someone like such as myself living in such a diverse city like Los Angeles. But is interracial dating still taboo to some? Or has the notion of interracial dating evolved like our societies and culture have over time?…
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Chapters 24-25 – As the novel ends, Okonkwo finishes his role as the Tragic Hero. Look at the steps 9-12 and discuss how we see or don’t see Okonkwo go through these steps. Make sure to use specific examples from the text. 1 ½ pg.…
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3. The climax of this novel is when Santiago is struggling to turn himself into the wind, and depending in the result of this action, Santiago will be able to save his and the Alchemist live from dead. The chief of the tribesman would kill…
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The foundation of any network is some sort of pathway for digital data (bits) to move back and forth between connected agents. Cables, ranging from coaxial to optical, have long dominated this realm. However, wireless is increasingly emerging as a viable alternative to direct physical connection (Stanford University, 2003). Wireless includes many various mediums such as AM, FM, HD and SiriusXM radio. Broadcast and satellite TV, and most, if not all, internet access and cellphones, are now wireless.…
- 455 Words
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In this problem, we will do this problem using the discriminator developed in problems 4.26, and 4.28 to construct the Matlab simulation system.…
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