Sorry I ask this question again, because I haven't found any solution for my problem. My ISA Server is used to connect 2 network, private, and public. My Dial-Up users stay in private network & RADIUS is located in public network. My problem is, how to "pass" the RADIUS information (UDP format) form my dial-up users in the internal network through ISA Server to the RADIUS server in the external Network? The authentication request is sent from the RAS (Modem Pool) to the RADIUS. Here is the scheme. I use Patton 2960 as the RAS. The RADIUS is IC-RADIUS under Linux. ----------- ------- ---------- | Dial-Up |-------------| RAS |------------| ISA | | User |(10.1.x.x) | | (10.1.0.1)| Server | ----------- ------- ---------- (2xx.x.x.2)| | ------------ --------------|----------| Internet | | ------------ (2xx.x.x.3)| ---------- | RADIUS | | Server | ---------- --- Best regards, Robby Sirwaturai Nework Administrator Network Operation Center Maranatha Christian Univeristy