freeDiameter: An Open Source Framework for an Authentication, Authorization, and Accounting Infrastructure

Abstract

AAA (Authentication, Authorization, and Accounting) is one of the important functions indispensable for providing services on the Internet. Diameter Base Protocol was standardized in IETF as a successor of RADIUS, which is a widely used AAA protocol in the current Internet. Diameter solves the problems that RADIUS has such as support of multiple realms, reliable and secure message transport, and failover. There are several open source implementations of Diameter Base Protocol. However, none of them completely conforms to the specification. The first contribution of freeDiameter is that it is an open source of Diameter Base Protocol that completely conforms to the specification. It is written in C and based on a BSD-like license. In the Diameter architecture, a particular service on Diameter Base Protocol is defined as a Diameter application such as Diameter EAP application for WiFi network access control. The second contribution of freeDiameter is that the software architecture of freeDiameter makes it easy to implement Diameter applications as additional plug-ins. freeDiameter has already been distributed through our home page. freeDiameter with Diameter EAP application has been used in our laboratory for WiFi network access. It was also used for network control in the WIDE camp held in September 2010 for four days in which approximately 200 researchers attended. There was no problem on freeDiameter. This is good evidence of the stability of freeDiameter.