Difference between revisions of "XMPP 2.0"

The routing rules for stanzas addressed to the bare JID in XMPP 1.0 are blurry and don’t really match modern always-online but not necessarily in the view of the user multi-device use cases. This is why [https://xmpp.org/extensions/xep-0280.html Message Carbons (XEP-0280)] have been invented. They allow a device to tell the server that it wants to receive carbon-copies of all messages received by any resource of an account. This only affects <code>&lt;message/&gt;</code> stanzas (for presence, there is a well-defined broadcast-to-all-resources mechanism and IQs can only be addressed to a single resource).

However, throughout the history of XMPP, there have been XEPs which use messages to send data which is really only of interest for a single resource. Prime examples are [https://xmpp.org/extensions/xep-0047.html In-Band Bytestreams (XEP-0047)], privacy enhancing protocols such as the (in)famous OTR and (private messages from) [https://xmpp.org/extensions/xep-0045.html Multi-User Chat (XEP-0045)]. This lead to Message Carbon rules being hand-wavy and blurry, some of the behaviour being implementation-defined, depending on co-operating clients which do not speak Message Carbons themselves and other unfortunaties.