A technician is troubleshooting authentication issues on a server. It turns out the clock on the
server was 72 minutes behind. Setting the clock to the correct time fixed the issue. Given the
scenario, which of the following authentication methods was being used?

A.
Kerberos

B.
CHAP

C.
TACACS+

D.
RADIUS

Explanation:

Kerberos is a distributed authentication service that allows a process (a client) running on behalf of
a principal (a user) to prove its identity to a verifier (an application server, or just server) without
sending data across the network that might allow an attacker or the verifier to subsequently
impersonate the principal. Kerberos optionally provides integrity and confidentiality for data sent
between the client and server.