EDS-518A Series User’s Manual

Featured Functions

Message Exchange

Authentication

Clientserver (RADIUS)

EAPOL-Start

EAP-Request/Identity

EAP-Response/Identity

EAP-Request/OTP

EAP-Response/OTP

EAP-Success

RADIUS Access-Request

RADIUS Access-Challenge

RADIUS Access-Request

RADIUS Access-Accept

Port Authorized

EAPOL-Logoff

Port Unauthorized

1.When the supplicant receives an “EAP Request/Identity” frame, it sends an “EAP Response/Identity” frame with its username back to the authenticator.

2.If the RADIUS server is used as the authentication server, the authenticator relays the “EAP Response/Identity” frame from the supplicant by encapsulating it into a “RADIUS Access-Request” frame and sends to the RADIUS server. When the authentication server receives the frame, it looks up its database to check if the username exists. If the username is not present, the authentication server replies with a “RADIUS Access-Reject” frame to the authenticator if the server is a RADIUS server or just indicates failure to the authenticator if the Local User Database is used. The authenticator sends an “EAP-Failure” frame to the supplicant.

3.The RADIUS server sends a “RADIUS Access-Challenge,” which contains an “EAP Request” with an authentication type to the authenticator to ask for the password from the client. RFC 2284 defines several EAP authentication types, such as “MD5-Challenge,” “One-Time Password,” and “Generic Token Card.” Currently, only “MD5-Challenge” is supported. If the Local User Database is used, this step is skipped.

4.The authenticator sends an “EAP Request/MD5-Challenge” frame to the supplicant. If the RADIUS server is used, the “EAP Request/MD5-Challenge” frame is retrieved directly from the “RADIUS Access-Challenge” frame.

5.The supplicant responds to the “EAP Request/MD5-Challenge” by sending an “EAP Response/MD5-Challenge” frame that encapsulates the user’s password using the MD5 hash algorithm.

6.If the RADIUS server is used as the authentication server, the authenticator relays the “EAP Response/MD5-Challenge” frame from the supplicant by encapsulating it into a “RADIUS Access-Request” frame along with a “Shared Secret,” which must be the same within the authenticator and the RADIUS server, and sends the frame to the RADIUS server. The RADIUS server checks against the password with its database, and replies with “RADIUS Access-Accept” or “RADIUS Access-Reject” to the authenticator. If the Local User Database is used, the password is checked against its database and indicates success or failure to the authenticator.

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