Kdbus meets linux-kernel

> One of the major DBUS features is multicasting and asynchronous signals.

Just two simple questions, from a non specialist:
DBUS requests looks a bit like SNMP, and even if SNMP docs is real crap it is reasonably easy to use - what would be the major difference between them?
(It would be nice to be able to ask another computer which timezone it is living in)

Adding multicast to AF_UNIX sockets is maybe wrong, but is it really less efficient to talk over an IP sockets to localhost (some short-circuit and zero copy network drivers are already probably implemented, isn't it)?