1 INTRODUCTION 1.1 USES OF COMPUTER NETWORKS 1.1.1 Business Applications 1.1.2 Home Applications 1.1.3 Mobile Users 1.1.4 Social Issues 1.2 NETWORK HARDWARE 1.2.1 Local Area Networks 1.2.2 Metropolitan Area Networks 1.2.3 Wide Area Networks 1.2.4 Wireless Networks 1.2.5 Home Networks 1.2.6 Internetworks 1.3 NETWORK SOFTWARE 1.3.1 Protocol Hierarchies 1.3.2 Design Issues for the Layers 1.3.3 Connection-Oriented and Connectionless Services 1.3.4 Service Primitives 1.3.5 The Relationship of Services to Protocols 1.4 REFERENCE MODELS 1.4.1 The OSI Reference Model 1.4.2 The TCP/IP Reference Model 1.4.3 A Comparison of the OSI and TCP/IP Reference Models 1.4.4 A Critique of the OSI Model and Protocols 1.4.5 A Critique of the TCP/IP Reference Model 1.5 EXAMPLE NETWORKS 1.5.1 The Internet 1.5.2 Connection-Oriented Networks:X.25,Frame Relay,and ATM 1.5.3 Ethernet 1.5.4 Wireless LANs:802.11 1.6 NETWORK STANDARDIZATION 1.6.1 Who?s Who in the Telecommunications World 1.6.2 Who?s Who in the International Standards World 1.6.3 Who?s Who in the Internet Standards World 1.7 METRIC UNITS 1.8 OUTLINE OF THE REST OF THE BOOK 1.9 SUMMARY 2 THE PHYSICAL LAYER 2.1 THE THEORETICAL BASIS FOR DATA COMMUNICATION 2.1.1 Fourier Analysis 2.1.2 Bandwidth-Limited Signals 2.1.3 The Maximum Data Rate of a Channel 2.2 GUIDED TRANSMISSION MEDIA 2.2.1 Magnetic Media 2.2.2 Twisted Pair 2.2.3 Coaxial Cable 2.2.4 Fiber Optics 2.3 WIRELESS TRANSMISSION 2.3.1 The Electromagnetic Spectrum 2.3.2 Radio Transmission 2.3.3 Microwave Transmission 2.3.4 Infrared and Millimeter Waves 2.3.5 Lightwave Transmission 2.4 COMMUNICATION SATELLITES 2.4.1 Geostationary Satellites 2.4.2 Medium-Earth Orbit Satellites 2.4.3 Low-Earth Orbit Satellites 2.4.4 Satellites versus Fiber 2.5 THE PUBLIC SWITCHED TELEPHONE NETWORK 2.5.1 Structure of the Telephone System 2.5.2 The Politics of Telephones 2.5.3 The Local Loop:Modems,ADSL,and Wireless 2.5.4 Trunks and Multiplexing 2.5.5 Switching 2.6 THE MOBILE TELEPHONE SYSTEM 2.6.1 First-Generation Mobile Phones:Analog Voice 2.6.2 Second-Generation Mobile Phones:Digital Voice 2.6.3 Third-Generation Mobile Phones:Digital Voice and Data 2.7 CABLE TELEVISION 2.7.1 Community Antenna Television 2.7.2 Internet over Cable 2.7.3 Spectrum Allocation 2.7.4 Cable Modems 2.7.5 ADSL versus Cable 2.8 SUMMARY 3 THE DATA LINK LAYER 4 THE MEDIUM ACCESS CONTROL SUBLAYER 5 THE NETWORK LAYER 6 THE TRANSPORT LAYER 7 THE APPLICATION LAYER 8 NETWORK SECURITY 9 READING LIST AND BIBLIOGRAPHY INDEX