Remote Access Server Authentication

C.

The answer to this question is C. TACACS.

TACACS (Terminal Access Controller Access-Control System) is a protocol used by network devices (such as routers, switches, and firewalls) to control access to network resources. It provides a centralized authentication, authorization, and accounting (AAA) framework to control access to network devices and services.

When a user tries to access a network resource, such as a router or a switch, TACACS uses a remote access server (RAS) to forward the user's logon password to an authentication server, such as a domain controller or a RADIUS server. The authentication server then verifies the user's credentials and sends an access or deny message to the network device via the remote access server.

TACACS is often used in enterprise networks where there are multiple network devices and users with different levels of access. It provides a granular level of control over who can access what resources, and it allows network administrators to track and audit user activity.

WPA2-PSK (Wi-Fi Protected Access II with Pre-Shared Key) and AES (Advanced Encryption Standard) are security protocols used to secure wireless networks and data. They are not used for authentication or access control.

TKIP (Temporal Key Integrity Protocol) is an encryption protocol used with WPA to secure wireless networks. It is also not used for authentication or access control.