FreeRADIUS

FreeRADIUS is a free open source RADIUS server.It offers an alternative to other enterprise RADIUS servers, as it is one of the most modular and feature-rich RADIUS servers available today. It is also within the top 5 RADIUS servers world-wide in terms of number of deployments, and number of users who are authenticated with it every day.It scales from embedded systems with small amounts of memory, to systems with multiple millions of users. It is fast, flexible, configurable, and supports more authentication protocols than many commercial servers. The server comes with a PHP based web user administration tool, called dialupadmin. It is currently used as the foundation for multiple commercial RADIUS products.
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