MUC Extensions
This page gathers the different ways the MUC (XEP-0045) has been extended over the years, in the MUC document itself but not exactly defined or by additional documents. Some of this page may overlap with XEP-Remarks/XEP-0045:_Multi-User_Chat.
Multi-Session Nick
If allowed by the service, a user can associate more than one full JID with the same occupant JID (e.g., the user juliet@capulet.lit is allowed to log in simultaneously as the nick "JuliC" in the characters@chat.shakespeare.lit chatroom from both juliet@capulet.lit/balcony and juliet@capulet.lit/chamber). Multi-session nicks are not currently defined in this document.
Identification
XEP-0421 Anonymous unique occupant identifiers for MUCs Allows for actions to be associated to a unique identifier when the JID isn't visible.
Moderation
XEP-0425 Message Moderation Allows a moderator to retract messages from other participants.
Invitations
XEP-0249: Direct MUC Invitations Defines a method for inviting a contact to a multi-user chat room directly, instead of sending the invitation through the chat room (mediated invites).
This may be useful if a user blocks messages from unknown JIDs.
Federation / Decentralization
XEP-0281: DMUC1: Distributed Multi-User Chat Defines methods for distributing Multi-User Chat (MUC) rooms across multiple chat services.
XEP-0289: Federated MUC for Constrained Environments Provides a protocol for federating MUC rooms together in order to reduce the effects of constrained network (e.g. unreliability, severely limited bandwidth) on the room occupants.
Optimisations
XEP-0436: MUC presence versioning
Reduces the amount of presence trafic
XEP-0437: Room Activity Indicators
Provides a mechanism for activity notifications in MUC
XEP-0463: MUC Affiliations Versioning
Reduces the amount of queries necessary to stay up-to-date with affiliations in a MUC room, while getting rid of races.