What is "xmpp"
XMPP (Extensible Messaging and Presence Protocol) is an open protocol, the standard for real-time communication. The protocol is commonly used in instant messaging applications (IM) and is the standard around which Gtalk, Facebook Chat, and other IM systems. It can also be leveraged for multi-user chat, collaboration, voice and video, middleware light, and many other applications.
XMPP works by starting a bidirectional XML stream between two entities. The stream is used to transport XMPP instances, which are small, well-defined XML blocks.
There are several XMPP servers available for use. For more comprehensive lists of server and client deployments, as well as XMPP libraries, visit xmpp org..