A central authentication server in 802.1X provides consistency in authentication across the network. True or False?

• A. True
• B. False
• C. Partially true
• D. Not sure

Answer: (A)

In 802.1X, authentication decisions are centralized on a single authentication server (typically a RADIUS server). The supplicant proves its identity to the authenticator (such as a switch or wireless access point), which forwards the credentials to the authentication server. The server evaluates the credentials against its user database and policy and returns an allow or deny, along with any authorization details like VLAN assignment or ACLs. Because the same server and policies apply regardless of which switch or AP a client connects through, the outcome of authentication is consistent across the network. If you have redundancy with multiple servers, ensure they share the same policies so consistency is maintained. An important caveat is that if the server isn’t reachable, authentication may fail or fall back to a different method, but when the server is available, the results are consistently enforced across the network.