Cisco® Secure Internet Security Solutions

AAA Authentication Setup with TACACS+ and RADIUS

To authenticate large numbers of users, you need to have a database that stores the usernames and passwords. This is where either TACACS+ or RADIUS servers come into play.

On the router configuration, TACACS+ and RADIUS are not difficult to configure. They also allow for multiple forms of authentication, including:

• Digital certificates

• One-time passwords

• Changeable passwords

• Static passwords

• UNIX authentication using the /etc/password file

• NT database authentication

Three steps are required to make a router use AAA:

Step 1.	Initial configuration
Step 2.	Building a method list
Step 3.	Linking the list to interfaces

Each of these will be discussed in turn.

Initial Configuration

You need to know a ...