Routing users after authentication to different sites/applications preserving the security context?

Hi!
We want to authenticate our users on our main site (default port 80, default.aspx, login page) and once a user successfully authenticated, we go grab a list of possible urls for that user and present it as links. Once the users clicks a link, we want to preserve the authentication context so that the app living on the chosen url does not have to re-authenticate the user.
Is something like that possible?
Is it recommended to do something like that?
Are there other ways to route users to their destination?
 
Thanks in advance, regards,
SiKo.
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