How does ajax push work?

Question

In simple terms, how is push achieved through ajax? Is this done through the same object used for conventional ajax requests?

Answer 1

Wikipedia has a simple definition of the Comet model, used to make AJAX push work

Answer 2

In simple terms, how is push achieved through ajax?

The general idea is to always have a request to the server "hanging", so the server can respond to it whenever it wants to "push" something to the client.

Is this done through the same object used for conventional ajax requests?

It can be, but you can emulate it with an iframe as well. This field is in very active development currently, so maybe WebSockets and the EventSource should be mentioned here as well.

Answer 3

http://en.wikipedia.org/wiki/Reverse_Ajax

It might be the standard in HTML5

http://en.wikipedia.org/wiki/Server-sent_events