[skMed]

Could you take a look at SignalR? (http://www.hanselman.com/blog/AsynchronousScalableWebApplica...)

* Since this is dealing with async operations, an IIS worker thread takes an incoming request and hands it off to be processed on the CLR thread pool. At this point, the IIS worker thread immediately becomes available for processing more requests

* Threadpool threads will not be tied up by open connections and waiting for IO. Only when executing actual code/work will they be in use

* To explain why threadpool threads are not tied up: Async operations use async IO. As soon as an I/O operation begins, that calling thread is returned to the thread pool to continue other work. When I/O completes, signal is sent and another thread is picked up to finish up work.