Understanding the Atmosphere Protocol

The Atmosphere Framework uses a really simple communication protocol between its supported client and the core server component. By default, Atmosphere attach, to the request URI, a list of query string that are used by the core server component. It can also set those value as requests headers if required. The mandatory key/value lists are:

• X-Atmosphere-Framework = The lowest Atmosphere's version supported
• X-Cache-Date = This header is used to retrieve lost events on the server side. Lost events happens when the browser reload the page, when the connection gets closed or any I/O related issue. The client always first set that value to 0, and after always use the value send back by the server, as a response's header. If the server's value cannot be retrieved, the value should be set to 0 and the server will figure out which events to send back.
• X-Atmosphere-Transport: <sse|websocket|long-polling|streaming|ajax|jsonp> The transport used for that connection.
• X-Atmosphere-tracking-id: Originally set to 0, this value will be set by the server in order to uniquely track the client.