Communication Networks Sharam Hekmat
PragSoft Corporation
Contents
Contents 6
Preface 10
1. Introduction 1
1.1. Network Components 2
1.2. Network Types 2
1.3. The OSI Model 4
1.3.1. The Physical Layer 7
1.3.2. The Data Link Layer 7
1.3.3. The Network Layer 8
1.3.4. The Transport Layer 9
1.3.5. The Session Layer 9
1.3.6. The Presentation Layer 10
1.3.7. The Application Layer 10
1.4. Protocol Notations 11
1.4.1. Service Primitives 11
1.4.2. Sequence Diagrams 12
1.4.3. State Transition Diagrams 12
1.5. Standards 13
1.6. Further Reading 14
1.7. Summary 15
1.8. Exercises 16
2. The Physical Layer 18
2.1. Equipment 19
2.1.1. Equipment Types 19
2.1.2. Connection Types 19
2.2. Transmission 20
2.2.1. Signal Types 20
2.2.2. Modulation 21
2.2.3. Digitization 22
2.2.4. Synchronization 23
2.2.5. Transmission Media 24
2.3. Multiplexing 27
2.3.1. Space Division Multiplexing (SDM) 28
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2.3.2. Frequency Division Multiplexing (FDM) 28
2.3.3. Time Division Multiplexing (TDM) 29
2.3.4. Concentration 29
2.4. Physical Layer Standards 30
2.4.1. RS-232 30
2.4.2. CCITT X.21 32
2.5. Further Reading 33
2.6. Summary 33
2.7. Exercises 34
3. The Data Link Layer 36
3.1 Link Protocol Types 37
3.1.1. Synchronous Protocols 37
3.1.2. Asynchronous Protocols 38
3.1.3. Master-Slave Protocols 38
3.1.4. Peer-to-Peer Protocols 38
3.2. Link Protocol Functions 38
3.2.1. Acknowledgments 39
3.2.2. Timers 39
3.2.3. Error Checking 40
3.2.4. Retransmission 42
3.2.5. Flow Control 42
3.3. Sliding Window Protocol 43
3.4. Data Link Layer Standards 45
3.4.1. BSC 45
3.4.2. HDLC 46
3.5. Further Reading 48
3.6. Summary 49
3.7. Exercises 50
4. The Network Layer 52
4.1. Network Services 53
4.2. Switching Methods 55
4.2.1. Circuit Switching 55
4.2.2. Packet Switching 57
4.3. Packet Handling 59
4.3.1. Packet Structure 60
4.3.2. Routing 60
4.3.3. Congestion Control 63
4.3.4. Error Handling 63
4.4. Internetworking 64
4.4.1. Network Sublayers 65
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4.5. Network Layer Standards 66
4.5.1. CCITT X.25 66
4.5.2. CCITT X.75 69
4.5.3. IP 70
4.5.4. ISO 8473 71
4.6. Further Reading 72
4.7. Summary 72
5. The Transport Layer 65
5.1. Transport Services 65
5.1.1. Network Types 67
5.2. Transport Protocol 67
5.2.1. TPDUs 67
5.2.2. Classes of Protocol 68
5.2.3. Segmentation 69
5.2.4. Multiplexing 69
5.2.5. Splitting and Recombining 69
5.2.6. Addressing 69
5.2.7. Flow Control 70
5.2.8. Error Checking 70
5.3. Transport Layer Standards 70
5.3.1. TCP 71
5.4. Further Reading 72
6. The Session Layer 74
6.1. Session Services 74
6.1.1. Session Layer Role 77
6.1.2. Functional Units 77
6.2. Session Protocol 78
6.2.1. Tokens 79
6.2.2. Activities and Dialogue Units 79
6.2.3. Synchronization 80
6.2.4. Error Reporting and Resynchronization 81
6.2.5. SPDUs 82
6.3. Session Layer Standards 82
6.4. Further Reading 83
7. The Presentation Layer 84
7.1. Presentation Services 84
7.1.1. Syntax 84
7.1.2. Service Primitives 87
7.1.3. Functional Units 89
7.2. Abstract Syntax Notation One 89
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7.2.1. Definitions in ASN.1 89
7.2.2. Basic Encoding Rules 91
7.3. Presentation Protocol 93
7.4. Presentation Standards 94
7.5. Further Reading 94
8. The Application Layer 95
8.1. Application Services 95
8.1.1. Application Entity 96
8.2. Common Application Service Elements 97
8.2.1. Association Control 97
8.2.2. Reliable Transfer 97
8.2.3. Remote Operations 98
8.3. Specific Application Service Elements 98
8.3.1. Virtual Terminal 98
8.3.2. Message Handling Systems 100
8.3.3. File Transfer, Access, and Management 104
8.4. Other Standards 108
8.5. Further Reading 108
9. Local Area Networks 109
9.1. Basic Concepts 109
9.1.1. Topologies and Access Protocols 110
9.1.2. Architecture 112
9.1.3. Transmission 113
9.2. IEEE 802 Standards 113
9.2.1. Logical Link Control 114
9.2.2. CSMA/CD 115
9.2.3. Token Bus 116
9.2.4. Token Ring 117
9.3. ANSI FDDI Standard 118
9.3.1. Topology 118
9.3.2. Token Ring Protocol 119
9.4. Further Reading 120
10. Telephone Networks 121
10.1. Basic Concepts 121
10.1.1. A Simple Network 122
10.1.2. Networks Topologies 123
10.1.3. Switching Systems 125
10.2. Signaling 126
10.2.1. Subscriber Signaling 127
10.2.2. Interexchange Signaling 128
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10.2.3. Common Channel Signaling 129
10.3. Signaling System Number 7 131
10.3.1. Signaling Data Link 132
10.3.2. Signaling Link Control 132
10.3.3. Signaling Network Functions 133
10.3.4. Signaling Connection Control Part 134
10.3.5. User Parts 135
10.3.6. Operations and Maintenance Applications Part 136
10.4. Private Telephone Networks 136
10.4.1. PBX Networks 136
10.4.2. Corporate Networks 137
10.4.3. Intelligent Networks 138
10.5. Further Reading 139
11. Integrated Services Digital Network 140
11.1. Basic Concepts 140
11.1.1. ISDN Channels 141
11.1.2. Functional Groupings and Reference Points 142
11.1.3. ISDN Services 144
11.2. Protocol Architecture 145
11.2.1. The Physical Layer 146
11.2.2. The Data Link Layer 148
11.2.3. The Network Layer 151
11.3. Frame Relay 154
11.3.1. V.120 155
11.3.2. Frame Relay 156
11.4. Internetworking 157
11.5. ISDN Standards 158
11.6. Further Reading 159
12. Broadband ISDN and ATM 161
12.1. Broadband ISDN 161
12.1.1. B-ISDN Services 161
12.1.2. B-ISDN User-Network Interface 163
12.1.3. B-ISDN Protocol Architecture 164
12.2. Asynchronous Transfer Mode 165
12.2.1. Channels and Paths 165
12.2.2. ATM Cells 167
12.3. Physical Layer 168
12.3.1. SDH-Based Interface 168
12.3.2. Cell-Based Interface 169
12.3.3. Cell Delineation 170
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12.3.4. HEC Generation and Verification 171
12.3.5. Cell Rate Decoupling 171
12.4. ATM Layer 172
12.4.1. Generic Flow Control 172
12.4.2. Virtual Path Identifier 172
12.4.3. Virtual Channel Identifier 172
12.4.4. Payload Type 173
12.4.5. Cell Loss Priority 173
12.5. ATM Adaptation Layer 173
12.5.1. Segmentation and Reassembly Sublayer 174
12.5.2. Convergence Sublayer 175
12.6. B-ISDN Standards 175
12.7. Further Reading 175
Bibliography 160
