The book is organized into seventeen chapters. After providing a basic introduction to Networking, Data Communications, and TCP/IP in the first-six chapters, we have covered Internet Protocol Version 6 (IPv6) greatly improves on IPv4 by vastly increasing the number of available addresses and by enabling more efficient routing, simpler configuration, built-in IP security, better support for real-time data delivery, and other essential enhancements in Chapter 7 of Internet Protocol Version 6. It also describes transition technologies that allow you to deploy IPv6 in IPv4 intranets and across the IPv4 Internet. Chapter 8 entitled ';Network Security' describes the Computer Crime Evolution, Network Security Concepts, Network Security Design, Networking Auditing, Site Auditing, Threat Agent Assessment, Security Domain, Firewall and its Types, Demilitarized (DMZ), Risk Management, Network Threats, Preventive Measures, Security Management, etc.