The Practice of Network Security: Deployment Strategies for Production Environments

6.1. Kerberos

Kerberos is the protocol most often associated with the AAA framework. Kerberos was originally developed for Unix-based systems and is defined in RFC 1510. Kerberos is an authentication infrastructure used to ensure the identity of users and systems on a network. The current version of Kerberos is 5.0, and there are Kerberos clients for almost every operating system.

Kerberos relies on a combination of key encryption and cryptographic protocols to ensure the authentication of users. The process, outlined in Figure 6.2, is fairly simple; a network administrator sets up an authentication server, known as a Ticket Granting Server (TGS). One or more realms (usually domains) are created on the TCG. A user requesting access to a particular ...