While configuring a new access layer switch, the administrator, Joe, was advised that he needed
to make sure that only devices authorized to access the network would be permitted to login and
utilize resources. Which of the following should the administrator implement to ensure this
happens?

A.
Log Analysis

B.
VLAN Management

C.
Network separation

D.
802.1x

Explanation:
802.1x is a port-based authentication mechanism. It’s based on Extensible Authentication Protocol
(EAP) and is commonly used in closed-environment wireless networks. 802.1x was initially used to
compensate for the weaknesses of Wired Equivalent Privacy (WEP), but today it’s often used as a
component in more complex authentication and connection-management systems, including
Remote Authentication Dial-In User Service (RADIUS), Diameter, Cisco System’s Terminal
Access Controller Access-Control System Plus (TACACS+), and Network Access Control (NAC).