FTOS Configuration Guide for the C-Series - Force10 Networks

Figure 474 RADIUS Frame Format
Code Identifier Length Message-Authenticator
Attribute
Range: 1-4
Codes: 1: Access-Request
2: Access-Accept
3: Access-Reject
11: Access-Challenge
The authentication process involves three devices:
• The device attempting to access the network is the supplicant. The supplicant is not allowed to
communicate on the network until the port is authorized by the authenticator. It can only communicate
with the authenticator in response to 802.1X requests.
• The device with which the supplicant communicates is the authenticator. The authenicator is the gate
keeper of the network. It translates and forwards requests and responses between the authentication
server and the supplicant. The authenticator also changes the status of the port based on the results of
the authentication process. The Force10 switch is the authenticator.
• The authentication-server selects the authentication method, verifies the information provided by the
supplicant, and grants it network access privileges.
Ports can be in one of two states:
• Ports are in an unauthorized state by default. In this state, non-802.1X traffic cannot be forwarded in
or out of the port.
• The authenticator changes the port state to authorized if the server can authenticate the supplicant. In
this state, network traffic can be forwarded normally.
Note: The Force10 switches place 802.1X-enabled ports in the unathorized state by default.
The Port-authentication Process
The authentication process begins when the authenticator senses that a link status has changed from down
to up:
1. When the authenticator senses a link state change, it requests that the supplicant identify itself using an
EAP Identity Request Frame.
2. The supplicant responds with its identity in an EAP Response Identity frame.
Type
(79)
EAP-Message Attribute
Length EAP-Method Data
(Supplicant Requested Credentials)
3. The authenticator decapsulates the EAP Response from the EAPOL frame, encapulates it in a
RADIUS Access-Request frame, and forwards the frame to the authentication server.
fnC0034mp
FTOS Configuration Guide, version 7.7.1.0 675