I just had a chance to work with SignalR – (Async library for .NET to help build real-time, multi-user interactive web applications | http://signalr.net/) for the CliniclMS – Clinic Intranet/Internet Application.
There are already some good walkthroughs about this on the SignalR github site (https://github.com/SignalR/SignalR) so as a warm-up I suggest you take a look at those. Both the low-level API and high-level API are interesting
The main difference is the amount of control you have over the connection and message processing. In the low-level API you have full control over this including being able to override what happens when a client connects, processing of messages, and even disconnection of the client. With the high-level API you for-go this for a much simpler implementation, in this case simpler does not mean less powerful or useful. I think in most cases the high-level API (hubs) will be the right approach and will have plenty of flexibility for what we are trying to accomplish.
Demo: Will Update Soon
Source Code: Will Update Soon