I have a web page written in CGI. This page has the userID and password information and authenticates the users. On the other hand I have an asp.net page that takes userID as input parameter and shows some sensitive data based on the userID. Can anyone tell me how I can encrypt the userID in CGI, so I can send the encrypted userID to the asp.net page? Does anybody know any other way? I would really appreciate any help. Thanks, Sohi.