RackSwitch G8000 Application Guide

EAPoL message exchange

During authentication, EAPOL messages are exchanged between the client and the G8000 authenticator, while RADIUS-EAP messages are exchanged between the G8000 authenticator and the RADIUS server.

Authentication is initiated by one of the following methods:

„The G8000 authenticator sends an EAP-Request/Identity packet to the client

„Client sends an EAPOL-Start frame to the G8000 authenticator, which responds with an EAP-Request/Identity frame.

The client confirms its identity by sending an EAP-Response/Identity frame to the G8000 authenticator, which forwards the frame encapsulated in a RADIUS packet to the server.

The RADIUS authentication server chooses an EAP-supported authentication algorithm to verify the client’s identity, and sends an EAP-Request packet to the client via the G8000 authenticator. The client then replies to the RADIUS server with an EAP-Response containing its credentials.

Upon a successful authentication of the client by the server, the 802.1X-controlled port transi- tions from unauthorized to authorized state, and the client is allowed full access to services through the controlled port. When the client later sends an EAPOL-Logoff message to the G8000 authenticator, the port transitions from authorized to unauthorized state.

If a client that does not support 802.1X connects to an 802.1X-controlled port, the G8000 authenticator requests the client's identity when it detects a change in the operational state of the port. The client does not respond to the request, and the port remains in the unauthorized state.

NOTE When an 802.1X-enabled client connects to a port that is not 802.1X-controlled, the cli- ent initiates the authentication process by sending an EAPOL-Start frame. When no response is received, the client retransmits the request for a fixed number of times. If no response is received, the client assumes the port is in authorized state, and begins sending frames, even if the port is unauthorized.

42 „ Chapter 2: Port-based Network Access Control

BMD00041, November 2008

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Blade ICE G8000 manual EAPoL message exchange