Can I Get MOSS Logged user from the MOSS session using ASP .NET

Hi,

I have given link to my web application from the MOSS site. When any user clicks the links from the MOSS site I need my web application to get MOSS logged in user id for the single sign on purpose.

Currently what I'm doing is, in the MOSS site i have created the application link with encrypted user id read from moss which I feel that not secure. So insted of passing the encrypted user id from moss to my web application, can I read the MOSS looged in user ID from my web application and so the authentication.

regards,
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