TekRADIUS is a freeware RADIUS server. You're free to use it for both commercial and personal use. We only ask you to provide feedback.

TekRADIUS complies with RFC 2865 and RFC 2866. It currently supports just Microsoft SQL Server. It runs as a Windows Service and comes with a Win32 management interface. You can log session details into a log file or to Event Log. You can select IP address to be listened and RADIUS Authentication and Accounting ports. You can optionally run it in Authorization only mode and you can turn off Accounting if you wish. You can also define your own Authorization SQL SELECT clause.