Take a look at this link:

http://www.codeproject.com/aspnet/aspnetsinglesignon.asp

HTH
 Braulio

/// ------------------------------
/// Braulio Diez
///
/// http://www.tipsdotnet.com
/// ------------------------------

Hi Sudha,
one way you can go if your applications are sitting on the same server is to
modify directory structure. Create one virtual directory with two
subdirectories (also virtual). Put your application into those sub
directories and login page into top directory.
Another more common way is described in Altair's post on Code Project as
already Braulio mentioned. This technique can be used only if your
application shares same subdomain.
If your application do not share subdomain you have to implement third
applicaton wich will log on users to your other applications. This is
possible if you  use cookiless authentication tickets and
enableCrossAppRedirects set to true:
  <authentication mode="Forms">
   <forms cookieless="UseUri" enableCrossAppRedirects="true" ... />
  </authentication>

Regards,
Ladislav