Which AAA function does not depend on the other two?

Authentication is the AAA function that does not depend on the other two functions—authorization and accounting. In networking and security contexts, authentication is the process of verifying the identity of a user or device. It occurs first in the sequence of AAA functions and ensures that only users or devices with valid credentials are granted access to a network or system.

Once authentication is successful, the system can proceed to authorization, which determines what an authenticated user is allowed to do, and accounting, which tracks the actions of that user. However, authentication can be performed independently; it does not require prior authorization or accounting to validate a user's identity. This autonomy is critical for establishing a secure base before any further actions regarding permissions or monitoring are considered.

Understanding the role of authentication as a standalone process highlights its significance in maintaining a secure network environment.