Network Security Defined — A Practical Guide to TCP/IP Network Security Terms and Concepts was created to serve as a resource for professionals around the world who need to provide for computer security within their organization and for the security of corporate information passing over world-wide networks. This one booklet does not replace a textbook on network security, but it can help you better understand general network security terms and concepts. The Introduction is a brief overview of the need for good network security and about planning and managing your network security needs. Chapter I describes network security, some things that can threaten security, and some ways to protect against those threats. Chapter II describes two encryption techniques and two methods to deliver encrypted data. Chapter III explains some authentication methods and describes some specific ways to deliver authentication services. Chapter IV contains the process for establishing a secure communication session using Kerberos, an authentication technique that uses encryption. Chapter V describes two major access control techniques to provide security and some specific examples of ways to deliver access control services. You’ll also find a list of sources for additional information about network security and a handy glossary at the end of this booklet.