This extensively revised, new edition of the 1998 Artech House classic, "Internet and Intranet Security", offers professionals an up-to-date and comprehensive understanding of the technologies that are available to secure TCP/IP-based networks, such as corporate intranets or the Internet, and their associated applications. It addresses firewall technologies to help practitioners provide access control service, and discusses the cryptographic protocols used to provide today's communication security services. From TCP/IP networking and cryptographic fundamentals, to firewall technologies, communication security protocols, and public key infrastructures, this handy reference offers practical guidance in utilizing cutting-edge technologies to secure various applications in the field of e-commerce and e-business. The book explores the rationale behind the security technologies that have been proposed and deployed on the Internet, and shows how to implement security mechanisms and corresponding protocol specifications.