In RADIUS central authentication, which component functions as the network access server that forwards authentication requests to the RADIUS server?

• A. Supplicant
• B. Authenticator
• C. Verifier
• D. RADIUS server

Answer: (B)

In RADIUS, the device that sits at the network edge and forwards credentials to the authentication server is the authenticator. The authenticator acts as the gateway between the user’s device (the supplicant) and the RADIUS server. When the supplicant tries to access the network, the authenticator forwards the user’s credentials as an Access-Request to the RADIUS server and then relays the server’s response back to the user. This forwarding role is what makes the authenticator the network access server in this model.

The supplicant is simply the client trying to gain access, and the RADIUS server is the entity that actually verifies the credentials and makes the access decision. There isn’t a standard role called verifier in this setup.