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In the above example, a wifi access point is providing access to the 192.168.254.0/24 network. When a device (called a supplicant) attempts to connect to the wifi network, the wireless access point starts an EAP conversation with the supplicant over 802.1X, requesting it to supply credentials. The access point then connects to the authentication server (which, in the example above is also part of the 192.168.254.0/24 network) and sends the EAP response it received from the supplicant over the RADIUS protocol in a packet of type Access-Request as one of the attributes. The authentication server may wish to request the supplicant for more information, it may thus answer the wifi access point with a RADIUS packet of type Access-Challenge containing an EAP message to be forwarded to the supplicant. The wifi access point facilitates this conversation between authentication server and supplicant until the authentication server sends a RADIUS packet to the NAS wifi access point which is of either type Access-Accept or Access-Reject.
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