As authorized by XEP-0053, the XMPP Registrar maintains registries of protocol namespaces and of various parameters that are used by the IETF's Extensible Messaging and Presence Protocol (XMPP) as well as by XMPP extensions published by the XMPP Standards Foundation. The following registries are available:
| Registry | HTML | XML |
|---|---|---|
| Alternative XMPP Connection Methods | HTML | XML |
| Advanced Message Processing Rule Actions | HTML | XML |
| Advanced Message Processing Rule Conditions | HTML | XML |
| Application-Specific Error Conditions | HTML | XML |
| Data Forms Validation Datatypes | HTML | XML |
| Data Forms Validation Datatype Prefixes | HTML | XML |
| FORM_TYPEs and Fields for Data Forms | HTML | XML |
| Jingle Application Formats | HTML | XML |
| Jingle Transport Methods | HTML | XML |
| Link-Local Messaging TXT Records | HTML | XML |
| Multi-User Chat Status Codes | HTML | XML |
| Nodes for Service Discovery and Publish-Subscribe | HTML | XML |
| Protocol Namespaces | HTML | XML |
| Service Discovery Features | HTML | XML |
| Service Discovery Identities | HTML | XML |
| SHIM Headers | HTML | XML |
| Stream Compression Methods | HTML | XML |
| Stream Features | HTML | XML |
| Stream Initiation Profiles | HTML | XML |
| XMPP URI/IRI Querytypes | HTML | XML |
The functions of the XMPP Registrar are managed by the XMPP Extensions Editor. Changes to the registries are announced on the Standards mailing list.