sharing authentication between classic asp and asp.net

Hi All,

I need help in understanding on how the following scenario will work.

Authentication will happen in classic ASP and when the user comes to a ASP.NET site, his authentication must be valid (single sign on, he need not sign in again).

I heard about sharing the authentication cookie among class asp and asp.net but I do not understand how will the cookie be shared. the classic asp and asp.net are two different sites and may live on different web servers over the internet.

Thanks.
JK
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