A wireless engineer must configure IEEE 802.1X authentication on a WLAN that supports new and legacy wireless devices. Which condition must be met for the legacy clients to be able to associate and au

The authenticator and authentication server communicate using RADIUS encapsulation, not a shared EAP protocol - the authenticator relays EAP messages transparently and does not negotiate EAP directly with the RADIUS server.

In 802.1X, the client (supplicant) and the authenticator (AP or WLC) exchange EAP messages over EAPOL at the wireless layer. The authenticator must support the same EAP authentication protocol as the client to properly facilitate the handshake. For legacy clients using older EAP types, the authenticator must also recognize and relay those protocols - if it does not, the association will fail before reaching the RADIUS server.

The 802.1X standard defines the relevant relationship as between the supplicant and the authenticator, not between the client and a controller specifically - 'controller' is too narrow and not the correct 802.1X terminology.

While EAP is ultimately negotiated end-to-end between the supplicant and the authentication server, the EAPOL exchange at the wireless link layer occurs between the client and the authenticator, making the authenticator's protocol support the binding constraint.