Bidirectional-Streams Over Synchronous HTTP, or BOSH (for more information on the specification, visit http://xmpp.org/extensions/xep-0124.html), is the XMPP name for a long polling style of interacting in real time with the browser. It uses or some would say abuses-standard HTTP to expose something akin to two-way real time communication between a client and a server.

BOSH works by opening a connection to the server and sending a stanza wrapped in a <body/> element (if required). The server will then hold open the connection until such time as it has something to send to the client, at which time it will send the stanza (again wrapped) and close the connection. The client will then re-establish a new connection immediately. If, until some predetermined timeout elapses (generally around 60 seconds), there is no stanza to send to the client, then the server will close the connection, again with the client re-establishing a connection immediately.

Each connection has a related...