Timeout for asynchonous web service calls

I hope this is the right forum for my question.

When a reference to a web service is created vs creates a proxy class. That class has a timeout property (actually it is inherited by the base class) that sets the timeout for synchronous calls. Is there a timeout for asynchronous calls? If I make an asyncronous call, for how long will client be avaiable to receive the response. Is there a limit to that?

What I want to do is make and asynchonous call make web server sleep for several hours (if not days) and responde after that period. Will the client receive the callback if the instance of the proxy class is still alive?

Thank in advance!

[668 byte] By [papadi] at [2007-12-22]