Normally, Web applications are not designed for duplex communications. Originally, HTTP was designed to support pure client-server. The problem here is to have
server push. Please see my past answer discussing related problems and the articles referenced below:
Application 'dashboard' for website accounts[
^],
http://en.wikipedia.org/wiki/Client-server_model[
^],
http://en.wikipedia.org/wiki/Server_push[
^],
http://en.wikipedia.org/wiki/Pull_technology[
^].
However, there are some ways to work around the problem; they are not very simple. First, you can think about having a duplex
Web Service. Please see this CodeProject article:
Duplex Web Services[
^].
You can also consider using some of the
server push approaches, in particular, SignalR (please see the links in my past answer referenced by my first link above).
—SA