Business Data Communications and Networking

Alan Dennis is a Fellow of the Association for Information Systems and a professor of information systems in the Kelley School of Business at Indiana University. He holds the John T. Chambers Chair in Internet Systems, which was established to honor John Chambers, president and chief executive officer of Cisco Systems, the worldwide leader of networking technologies for the Internet.Alexandra Durcikova is an Associate Professor at the Price College of Business, University of Oklahoma. Alexandra has a PhD in management information systems from the University of Pittsburgh. She has earned an MSc degree in solid state physics from Comenius University, Bratislava, worked as an experimental physics researcher in the area of superconductivity and as an instructor of executive MBA students prior to pursuing her PhD. Alexandra’s research interests include knowledge management and knowledge management systems, the role of organizational climate in the use of knowledge management systems, knowledge management system characteristics, governance mechanisms in the use of knowledge management systems, and human compliance with security policy and characteristics of successful phishing attempts within the area of network security. Her research appears in Information Systems Research, MIS Quarterly, Journal of Management Information Systems, Information Systems Journal, Journal of Organizational and End User Computing, International Journal of Human-Computer Studies, International Journal of Human-Computer Studies, and Communications of the ACM.Dr. Jerry FitzGerald wrote the early editions of this book in the 1980s. At the time, he was the principal in Jerry FitzGerald & Associates, a firm he started in 1977.

• About the Authors vPreface viPart One Introduction 1Chapter 1 Introduction to Data Communications 11.1 Introduction 11.2 Data Communications Networks 51.2.1 Components of a Network 61.2.2 Types of Networks 71.3 Network Models 81.3.1 Open Systems Interconnection Reference Model 91.3.2 Internet Model 101.3.3 Message Transmission Using Layers 121.4 Network Standards 141.4.1 The Importance of Standards 141.4.2 The Standards-Making Process 151.4.3 Common Standards 171.5 Future Trends 181.5.1 Wireless LAN and BYOD 181.5.2 The Internet of Things 181.5.3 Massively Online 191.6 Implications for Cyber Security 20Part Two Fundamental Concepts 27Chapter 2 Application Layer 272.1 Introduction 272.2 Application Architectures 282.2.1 Host-Based Architectures 292.2.2 Client-Based Architectures 302.2.3 Client–Server Architectures 302.2.4 Cloud Computing Architectures 332.2.5 Peer-to-Peer Architectures 352.2.6 Choosing Architectures 362.3 World Wide Web 372.3.1 How the Web Works 372.3.2 Inside an HTTP Request 382.3.3 Inside an HTTP Response 392.4 Electronic Mail 412.4.1 How Email Works 412.4.2 Inside an SMTP Packet 442.4.3 Attachments in Multipurpose Internet Mail Extension 452.5 Other Applications 452.5.1 Telnet 462.5.2 Videoconferencing 472.6 Implications for Cyber Security 48Chapter 3 Physical Layer 593.1 Introduction 593.2 Circuits 613.2.1 Circuit Configuration 613.2.2 Data Flow 623.2.3 Multiplexing 623.3 Communication Media 653.3.1 Twisted-Pair Cable 653.3.2 Coaxial Cable 653.3.3 Fiber-Optic Cable 663.3.4 Radio 673.3.5 Microwave 683.3.6 Satellite 683.3.7 Media Selection 703.4 Digital Transmission of Digital Data 713.4.1 Coding 713.4.2 Transmission Modes 723.4.3 Digital Transmission 733.4.4 How Ethernet Transmits Data 743.5 Analog Transmission of Digital Data 753.5.1 Modulation 753.5.2 Capacity of a Circuit 783.5.3 How Modems Transmit Data 783.6 Digital Transmission of Analog Data 793.6.1 Translating from Analog to Digital 793.6.2 How Telephones Transmit Voice Data 803.6.3 How Instant Messenger Transmits Voice Data 813.6.4 Voice over Internet Protocol (VoIP) 823.7 Implications for Cyber Security 83Chapter 4 Data Link Layer 914.1 Introduction 914.2 Media Access Control 924.2.1 Contention 924.2.2 Controlled Access 924.2.3 Relative Performance 934.3 Error Control 944.3.1 Sources of Errors 944.3.2 Error Prevention 964.3.3 Error Detection 974.3.4 Error Correction via Retransmission 984.3.5 Forward Error Correction 984.3.6 Error Control in Practice 994.4 Data Link Protocols 1004.4.1 Asynchronous Transmission 1014.4.2 Synchronous Transmission 1014.5 Transmission Efficiency 1044.6 Implications for Cyber Security 106Chapter 5 Network and Transport Layers 1145.1 Introduction 1145.2 Transport and Network Layer Protocols 1165.2.1 Transmission Control Protocol (TCP) 1165.2.2 Internet Protocol (IP) 1175.3 Transport Layer Functions 1185.3.1 Linking to the Application Layer 1185.3.2 Segmenting 1195.3.3 Session Management 1205.4 Addressing 1235.4.1 Assigning Addresses 1245.4.2 Address Resolution 1295.5 Routing 1315.5.1 Types of Routing 1325.5.2 Routing Protocols 1345.5.3 Multicasting 1365.5.4 The Anatomy of a Router 1375.6 TCP/IP Example 1385.6.1 Known Addresses 1405.6.2 Unknown Addresses 1415.6.3 TCP Connections 1425.6.4 TCP/IP and Network Layers 1435.7 Implications for Cyber Security 145Part Three Network Technologies 162Chapter 6 Network Design 1626.1 Introduction 1626.1.1 Network Architecture Components 1636.1.2 The Traditional Network Design Process 1646.1.3 The Building-Block Network Design Process 1666.2 Needs Analysis 1666.2.1 Network Architecture Component 1686.2.2 Application Systems 1696.2.3 Network Users 1696.2.4 Categorizing Network Needs 1706.2.5 Deliverables 1716.3 Technology Design 1716.3.1 Designing Clients and Servers 1716.3.2 Designing Circuits 1716.3.3 Network Design Tools 1746.3.4 Deliverables 1746.4 Cost Assessment 1746.4.1 Request for Proposal 1756.4.2 Selling the Proposal to Management 1756.4.3 Deliverables 1766.5 Implications for Cyber Security 176Chapter 7 Wired and Wireless Local Area Networks 1827.1 Introduction 1827.2 LAN Components 1837.2.1 Network Interface Cards 1837.2.2 Network Circuits 1847.2.3 Network Hubs, Switches, and Access Points 1857.2.4 Network Operating Systems 1887.3 Wired Ethernet 1897.3.1 Topology 1907.3.2 Media Access Control 1927.3.3 Types of Ethernet 1937.4 Wireless Ethernet 1947.4.1 Topology 1947.4.2 Media Access Control 1947.4.3 Wireless Ethernet Frame Layout 1967.4.4 Types of Wireless Ethernet 1967.4.5 Security 1987.5 The Best Practice LAN Design 1997.5.1 Designing User Access with Wired Ethernet 2007.5.2 Designing User Access with Wireless Ethernet 2007.5.3 Designing the Data Center 2037.5.4 Designing the e-Commerce Edge 2067.5.5 Designing the SOHO Environment 2067.6 Improving LAN Performance 2077.6.1 Improving Server Performance 2087.6.2 Improving Circuit Capacity 2107.6.3 Reducing Network Demand 2107.7 Implications for Cyber Security 210Chapter 8 Backbone Networks 2208.1 Introduction 2208.2 Switched Backbones 2218.3 Routed Backbones 2248.4 Virtual LANs 2278.4.1 Benefits of VLANs 2278.4.2 How VLANs Work 2298.5 The Best Practice Backbone Design 2328.6 Improving Backbone Performance 2338.6.1 Improving Device Performance 2338.6.2 Improving Circuit Capacity 2348.6.3 Reducing Network Demand 2348.7 Implications for Cyber Security 234Chapter 9 Wide Area Networks 2439.1 Introduction 2439.2 Dedicated-Circuit Networks 2449.2.1 Basic Architecture 2459.2.2 T-Carrier Services 2489.2.3 SONET Services 2499.3 Packet-Switched Networks 2509.3.1 Basic Architecture 2509.3.2 Frame Relay Services 2519.3.3 MPLS Services 2529.3.4 Ethernet Services 2529.4 Virtual Private Networks 2549.4.1 Basic Architecture 2549.4.2 VPN Types 2559.4.3 How VPNs Work 2569.5 The Best Practice WAN Design 2589.5.1 Software Defined WAN 2589.5.2 Choosing WAN Circuits 2599.6 Improving WAN Performance 2619.6.1 Improving Device Performance 2619.6.2 Improving Circuit Capacity 2619.6.3 Reducing Network Demand 2629.7 Implications for Cyber Security 262Chapter 10 The Internet 27410.1 Introduction 27410.2 How the Internet Works 27510.2.1 Basic Architecture 27510.2.2 Connecting to an ISP 27710.2.3 The Internet Today 27810.3 Internet Access Technologies 27910.3.1 Digital Subscriber Line 27910.3.2 Cable Modem 28010.3.3 Fiber to the Home 28210.4 The Future of the Internet 28310.4.1 Internet Governance 28310.4.2 Building the Future 28410.5 Implications for Cyber Security 285Part Four Network Management 292Chapter 11 Network Security 29211.1 Introduction 29211.1.1 Why Networks Need Security 29411.1.2 Types of Security Threats 29411.1.3 Network Controls 29511.2 Risk Assessment 29611.2.1 Develop Risk Measurement Criteria 29711.2.2 Inventory IT Assets 29811.2.3 Identify Threats 29911.2.4 Document Existing Controls 30111.2.5 Identify Improvements 30411.3 Ensuring Business Continuity 30411.3.1 Virus Protection 30411.3.2 Denial-of-Service Protection 30511.3.3 Theft Protection 30811.3.4 Device Failure Protection 30911.3.5 Disaster Protection 31011.4 Intrusion Prevention 31311.4.1 Security Policy 31411.4.2 Perimeter Security and Firewalls 31411.4.3 Server and Client Protection 32011.4.4 Encryption 32311.4.5 User Authentication 32911.4.6 Preventing Social Engineering 33211.4.7 Intrusion Prevention Systems 33311.4.8 Intrusion Recovery 33511.5 Best Practice Recommendations 33611.6 Implications for Your Cyber Security 338Chapter 12 Network Management 35212.1 Introduction 35212.2 Designing for Network Performance 35312.2.1 Managed Networks 35312.2.2 Managing Network Traffic 35712.2.3 Reducing Network Traffic 35812.3 Configuration Management 36112.3.1 Configuring the Network and Client Computers 36112.3.2 Documenting the Configuration 36212.4 Performance and Fault Management 36412.4.1 Network Monitoring 36412.4.2 Failure Control Function 36612.4.3 Performance and Failure Statistics 36812.4.4 Improving Performance 37012.5 End User Support 37112.5.1 Resolving Problems 37112.5.2 Providing End User Training 37212.6 Cost Management 37312.6.1 Sources of Costs 37312.6.2 Reducing Costs 37512.7 Implications for Cyber Security 377Appendices (Online)Glossary (Online)Index I-1