how to push data change notifications (oracle and sql server database) to relevant users (web browsers) using SignalR+ASP.NET MVC or Node.JS+WebSocket

Question

i have a windows based client server team task management application that i like to redevelop using html5, asp.net mvc4, css3 etc.

current system uses tcp sockets to update all relevant members when there is any update on the task listed in members task list.

i like to do same in the browsers and apple and android devices.  i dont want client to keep polling for the data change for example task status when changed from "assigned" to "working" using AJAX.

i surf web and found that it can be done either using asp.net mvc4 + signalr + web apis etc or by using node.js + websockets etc.

if more details are required, i can create a document and sent it.

any help would be highly appreciated.

Thanks