What is RADIUS?
RADIUS, short for Remote Authentication Dial-In User Service, is a protocol used for authentication, authorization, and accounting (AAA) in network systems. Developed in 1992 by Livingston Enterprises, it was originally designed for managing authentication information in dial-up internet connections and remote access over telephone lines. In 1997, RADIUS was standardized by the Internet Engineering Task Force (IETF) as RFC 2058, and subsequent RFC documents have further refined its specifications.
RADIUS operates on a client/server model, utilizing UDP/IP for communication. In RADIUS, the client refers to a device that provides network access or other services to users and requests authentication and accounting from the RADIUS server. The RADIUS server processes these requests and returns the outcomes to the client.
Although RADIUS is still widely used today, it has several limitations, such as constraints on the amount of data that can be included in packets, the lack of a feature for notifying reserved bandwidth for services like voice and video, and the absence of encryption standards. To address these issues, the Diameter protocol, an enhanced version of RADIUS, was introduced in 2003 as RFC 3588. Diameter is increasingly adopted by major service providers, particularly in mobile telecommunications.
F5’s BIG-IP platform supports a variety of authentication methods, including RADIUS. Additionally, F5 has developed solutions related to the Diameter protocol, demonstrating profound expertise in this area.