1. IEEE 802.1x
Authentication
Standard:

2. Terms:
 Supplicant - The User or Client to be
authenticated
 Radius Server – The Server doing the
authentication
 Authenticator – The device between the
Supplicant & the Radius Server
 EAPOL – (Extensible Authentication
Protocol Over LANs)

3. How it Works:
 The Authenticator sends an EAP request
packet to the Supplicant.
 The Supplicant sends an EAP packet to
the Authenticator.
 The Authenticator sends a packet to the
Radius Server.
 The Radius Server challenges the
Authenticator with a token or password.

4. How it Works: continued…
 The Authenticator changes it from the IP
to EAPOL.
 The Supplicant responds to the challenge
and passes it to the Authentication Server.
 If there’s a successful challenge, then the
Authentication Server responds with a
success message allowing access to the
LAN.

5. Example:

6. Key Aspects:
 Supplicant = End station software
 Authenticator = Wired switch or SSID
 AuthenticationServer = Ensures certificate
or passwords are correct

7. Benefits:
 IEEE
Standard 98% of all switches support
802.1x
 Good authentication
 ‘Pre-connect’ enforcement of access
policies

8. Drawbacks:
 Incompatibilities with certain switches
 Some security issues
 Tough to deploy
 Does not have a ‘post-connect’