AAA Framework

The AAA framework structures access control around three sequential concerns: Authentication verifies who is making the request, Authorization decides what they can do, and Accounting records what they actually did. Originally formalized for network access (dial-up, VPN, Wi-Fi) through protocols such as RADIUS, TACACS+ and Diameter, the model is now applied to cloud APIs, SaaS apps and zero-trust architectures. Separating the three concerns enables centralized identity stores, consistent policy enforcement and uniform audit trails across heterogeneous systems. AAA is often combined with multi-factor authentication, role-based access control and SIEM correlation to provide end-to-end identity governance.