Chapter 4. Authentication

This chapter zooms in on authentication. Authorization and accounting will follow later in the book.

Authentication is a process where we establish if someone is who he or she claims to be. The most common way is by a unique username and password.

In this chapter we shall:

• Discuss PAP, CHAP, and MS-CHAP authentication protocols
• See when and how authentication is done in FreeRADIUS
• Explore ways to store passwords
• Look at other authentication methods

So let's get on with it...