The AP's Authentication Service: RADIUS

An AP is configured to authenticate clients by using their Active Directory username and password.

The AP uses UDP to connect to the authentication service, which then queries Active Directory.

Which of the following authentication services is being used by the AP in this scenario?

A.

RADIUS

B.

TACACS+

C.

LDAP

D.

Kerberos.

A.

The authentication service being used by the AP (Access Point) in this scenario is RADIUS (Remote Authentication Dial-In User Service).

RADIUS is a popular authentication protocol used in many networks to authenticate and authorize remote users or devices attempting to access network resources. It is often used in conjunction with other authentication protocols, such as LDAP or Active Directory, to provide a central point of authentication and authorization for remote access.

In this scenario, the AP is configured to use the client's Active Directory username and password for authentication, but it uses RADIUS to communicate with the authentication service that queries Active Directory. When a client attempts to connect to the network, the AP sends the client's credentials to the RADIUS server, which then queries Active Directory to validate the credentials. If the credentials are valid, the RADIUS server sends a message back to the AP to grant the client access to the network.

TACACS+ (Terminal Access Controller Access Control System Plus) is another authentication protocol that is used to provide centralized authentication, authorization, and accounting (AAA) for network devices. However, it is not commonly used for wireless access authentication.

LDAP (Lightweight Directory Access Protocol) is a protocol used for accessing and maintaining distributed directory information services. It is often used in conjunction with other authentication protocols to provide centralized authentication and authorization.

Kerberos is a network authentication protocol used to provide secure communication over an untrusted network. It is often used in Windows-based networks, but it is not typically used for wireless access authentication.

Therefore, the correct answer to the question is A. RADIUS.