Internet Authentication Service is Microsoft's implementation of a Remote Authentication Dial-in User Service (RADIUS) server. ...

Internet Authentication Service is Microsoft's implementation of a Remote Authentication Dial-in User Service (RADIUS) server. IAS performs authentication, authorization, auditing and accounting for dial-up and virtual private network (VPN) remote access, for router-to-router connections, for wireless authentication and for machine health check. This feature adds IAS as a NT Service