BEEP

BEEP is a new Internet standards-track protocol framework for new Internet applications. BEEP as an Application Protocol Framework is a turbocharger for Internet applications that offers advanced features such as:

*(1) a standard application layer that supports dynamic, pluggable application 'profiles' [protocols]; 

• (2) peer-to-peer, client-server, or server-to-server capabilities;
• (3) multiple channels over a single authenticated session;
• (4) support for arbitrary MIME payloads, including XML;
• (5) a standard layer for session management..."

http://www.beepcore.org/