XMPP protocols are published in several forms:
- The core protocols are defined in RFC 6120, RFC 6121, and RFC 6122 as published by the Internet Engineering Task Force (IETF).
- Several related RFCs have been published as well.
- Various individuals and IETF working groups are working on other XMPP technologies in the form of Internet-Drafts.
- Finally, the XMPP Standards Foundation (XSF) publishes extensions to the core protocols in the form of XMPP Extension Protocols (XEPs).
A list of protocol namespaces is also available.