authentication, authorization, and accounting (AAA)

A set of protocols that mediate network access. For example, an AAA server identifies users using a process which entails verifying evidence of a digital identity, such as a digital certificate (authentication), and implements policies that determine which resources and services a valid user can access (authorization). Determined authorization is typically inherited during the authentication process, and refers to deciding if an entity has access restrictions, such as encryption. Accounting usually refers to keeping track of time and data resources used for billing and analysis (accounting).