Asp.Net concurrent requests from same session

You could run into a situation where you need to make multiple server requests from same browser page (or rather session). We would expect the requests to be served in parallel but they rather go sequential. Behavior of session-enabled requests handling by asp.net is important to be known to handle this case.

Session State is read-write for pages by default.
In this case, any request gets exclusive lock to the session object. So, the other requests from the same session (even if it requires only read access to the session) will have to wait until the lock is released either by completing the first request or timeout on the lock by first request.