Programming Jabber

The X::IQ Relationship

As has been noted, some of the X namespaces—autoupdate, conference, roster, and oob—have cousins in the IQ space. If you’re still confused about which to use where, there’s a rule of thumb about context: the IQ namespaces generally are used to qualify a conversation that revolves around whatever the namespace represents, while the X namespaces apply more to one-off, ad hoc, information-laden messages.

For example, the jabber:iq:conference namespace qualifies much of the content of a conversation between a user and the conferencing service regarding entry to a specific room. The jabber:x:conference namespace is used to provide context and meaning to a pointer to a room.

Likewise, the jabber:x:oob namespace qualifies a pointer to some piece of information that is out of band, whereas the jabber:iq:oob namespace provides context to a negotiation that leads to the usage of that external bandwidth.