Implementing Pub/Sub or SignalR functionality on .NET 3.5

[cohenoam]

Using SignalR, it is pretty easy to synchronise, distinct client PC browsers in realtime with inbuilt PUB/SUB mechanism. However SignalR can only be used with .NET 4.0 or above. We are trying to achieve similar functionality in .NET 3.5, since we can't upgrade our application at this point of time.Considering the fact that SignalR leverages following recent technologies -[*]Task Parallel Library in dot net 4.0[*]WebSockets in HTML5 For asynchronous calls we're planning to use classical BeginAsync and callback approach, & ThreadPool for creting multiple threads. Still learning how to use HTML 5 WebSocket.We're evaluating other alternatives as well like using jQuery AJAX & writing custom IIS Hander which could take async updates from Client 1 & push this to Client 2 and so on.If you have done something similar in past, Can you please suggest which approach would be correct to proceed with. Any new suggestion on this would also be helpful.Thank you for your time.