Jabber Builds Case For IM Standards. “XMPP is an open protocol widely used as the common connection between open source and proprietary IM systems. The JSF has been pushing hard to get the protocol ratified soon by the IETF. As a selling point, the JSF reports that more than 215,000 open source XMPP servers have been installed with a total worldwide user base of approximately 7-10 million people.”