Remote Authentication Dial-In User Service (RADIUS)

RADIUS is a client/server-based system that secures a Cisco network against intruders. Implemented in IOS, RADIUS sends authentication requests to a RADIUS server. Radius was created by Livingston Enterprises and is now defined in RFC 2138/2139.

A RADIUS server is a device that has the RADIUS daemon or application installed. RADIUS must be used with AAA to enable the authentication, authorization, and accounting of remote users when using Cisco IOS routers.

When a RADUIS server authenticates a user, the following events occur:

The user is prompted for and enters a username and password.
The username and encrypted password are sent over the network to the RADIUS server.
The user receives ...

Get CCIE Security Exam Certification Guide now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.