I have found below one on SOF. Check that.
Quote:
It's all about not associating 1 session with 1 user.
Let me briefly explain that.
Usually you've a server session in ASP.NET storing some user values that may customize or place useful data like this:
HttpContext.Current.Session["isAuthenticated"] = true;
What about:
HttpContext.Current.Session["1182"]["isAuthenticated"] = true;
...where "1182" is just an unique user identifier.
Just store values in server session in some collection where its key is the unique user identifier of authenticated identity, so this allows a parameterized-by-unique-user-identifier access to session's values.
It's an abbreviation of a more mature and complex actual solution, but it's a hint of how you'd handle such situation.
For more info check
Multiple Session or Multiple User login in same website/webapp at same time[
^].
I hope this will help to you.
[Edit member="Tadit"]
Link text added to reflect the Article/QA title.
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