SIMPLE (SIP for Instant Messaging and Presence Leveraging Extensions)

SIMPLE is an add-on to the Session Initiation Protocol (SIP) that some industry insiders predict will be the basis for a new Instant Messaging and Presence Protocol (IMPP). SIMPLE stands for SIP for Instant Messaging and Presence Leveraging Extensions. SIP was originally developed for voice over IP (VoIP), but has since incorporated support for Web conferencing, live video, and other media. SIMPLE is backed by Microsoft, IBM, Sun, Novell, and other industry leaders.