Is there a Microsoft equivalent for HTML5 Server-Sent Events?

To achieve your goal for HTML5 Server-Sent Events −

Try polyfill

It would work for IE10 and IE11 as well. It starts with −

if ("EventSource" in global) return;

It only runs in web browsers that do not support EventSource.

Refer the following Git

Try websockets 

Works for IE10 and IE 11 and it also provides bi-directional communication options.