TACACS

TACACS (Terminal Access Controller Access Control System), widely used in network environments, is a client/server protocol that enables remote access servers to communicate with a central server to authenticate dial-in users and authorize their access to the requested system or service. It is commonly used for providing NAS (Network Access Security). NAS ensures secure access from remotely connected users. TACACS implements the TACACS Client and provides the AAA (Authentication, Authorization and Accounting) functionalities.

TACACS is used for several reasons:

• Facilitates centralized user administration
• Uses TCP for transport to ensure reliable delivery
• Supports inbound authentication, outbound authentication and change password request for the Authentication service
• Provides some level of protection against an active attacker