Explanation AAA stands for Authentication, Authorization, and Accounting, and it is a framework that provides security services for network access control. Authentication verifies the identity of a user or device that requests access to a network resource. Authorization determines what level of access or privileges are granted to a user or device based on their identity or role. Accounting tracks and records the usage of network resources by users or devices for billing or auditing purposes. RADIUS (Remote Authentication Dial-In User Service) is a protocol that implements AAA functions by communicating with a central server that stores user credentials and policies.