Administrator Guide
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.
3 The authenticator decapsulates the EAP response from the EAPOL frame, encapsulates it in a RADIUS Access-Request frame and 
forwards the frame to the authentication server.
4 The authentication server replies with an Access-Challenge frame. The Access-Challenge frame requests that the supplicant prove 
that it is who it claims to be, using a specied method (an EAP-Method). The challenge is translated and forwarded to the supplicant 
by the authenticator.
5 The supplicant can negotiate the authentication method, but if it is acceptable, the supplicant provides the Requested Challenge 
information in an EAP response, which is translated and forwarded to the authentication server as another Access-Request frame.
6 If the identity information provided by the supplicant is valid, the authentication server sends an Access-Accept frame in which 
network privileges are specied. The authenticator changes the port state to authorized and forwards an EAP Success frame. If the 
identity information is invalid, the server sends an Access-Reject frame. If the port state remains unauthorized, the authenticator 
forwards an EAP Failure frame.
Figure 4. EAP Port-Authentication
802.1X
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