AAA and Network Security for Mobile Access: Radius, Diameter, EAP, PKI and IP Mobility

2.1. Examples of Authentication Mechanisms

In this section, we describe the most widespread legacy methods used for authentication mechanisms of users and messages. Some of these mechanisms may be considered inadequate from a security standpoint these days. However, we feel this overview will help us pave the way for discussing more sophisticated extensible authentication protocol (EAP) based authentication mechanisms, especially since EAP was originally designed as extension to legacy authentication mechanisms. We described how device authentication mechanisms are now gaining distinction and significance of their own, reading to more sophisticated methods for authentication of devices compared with those traditionally utilized for authentication of users. A few of the device authentication methods are highlighted in this section for completeness. In later chapters, we will provide more details on these more sophisticated authentication methods.

2.1.1. User Authentication Mechanisms

For a long time, users that needed to remotely access the network through wired connections were using dial-up services to a modem pool provided by the network operator. A majority of the dial-up services used a protocol called point-to-point protocol (PPP) that was designed to provide a number of link layer functionalities. Several user authentication mechanisms were designed for controlling access to the dial-up services to users. PPP was therefore designed to support facilities for performing several ...