From Wikipedia, the free encyclopedia

In computer security, AAA stands for “authentication, authorization and accounting”.

Authentication 

Authentication refers to the confirmation that a user who is requesting services is a valid user of the network services requested. Authentication is accomplished via the presentation of an identity and credentials. Examples of types of credentials are passwords, one-time tokens, digital certificates, and phone numbers (calling/called).

Authorization 

Authorization refers to the granting of specific types of service (including "no service") to a user, based on their authentication, what services they are requesting, and the current system state. Authorization may be based on restrictions, for example time-of-day restrictions, or physical location restrictions, or restrictions against multiple logins by the same user. Authorization determines the nature of the service which is granted to a user. Examples of types of service include, but are not limited to: IP address filtering, address assignment, route assignment, QoS/differential services, bandwidth control/traffic management, compulsory tunneling to a specific endpoint, and encryption.

Accounting 

Accounting refers to the tracking of the consumption of network resources by users. This information may be used for management, planning, billing, or other purposes. Real-time accounting refers to accounting information that is delivered concurrently with the consumption of the resources. Batch accounting refers to accounting information that is saved until it is delivered at a later time. Typical information that is gathered in accounting is the identity of the user, the nature of the service delivered, when the service began, and when it ended.

The AAA is sometimes combined with auditing and accordingly becomes AAAA.

• RFC 2194 Review of Roaming Implementations
• RFC 2477 Criteria for Evaluating Roaming Protocols
• RFC 2881 Network Access Server Requirements Next Generation (NASREQNG) NAS Model
• RFC 2903 Generic AAA Architecture
• RFC 2904 AAA Authorization Framework
• RFC 2905 AAA Authorization Application Examples
• RFC 2906 AAA Authorization Requirements
• RFC 3169 Criteria for Evaluating Network Access Server Protocols
• RFC 3539 AAA Transport Profile
• RFC 1234 AAA Transport Profile

• RADIUS
• DIAMETER
• TACACS
• TACACS+

Other protocols used in combination with the above :

• PPP
• EAP
• LDAP

• The webpage of Authentication, Authorization and Accounting IETF working group
• ActivIdentity 4TRESS AAA Server for Remote Access