On Thursday 13 January 2011 09:21:05 Kaiduan Xie wrote: > Hi, all, > > I am relatively new to XMPP world, and have a real problem to be > addressed. The problem is, user subscribes to a particular event, when > the event happens, system delivers an event notification to the > interested users as soon as possible. This is a classical PUB/SUB > system. One thing we need to consider is that the user may not stay > connected all the time, for example he steps out of wireless coverage. > We need to hold the event notification, and when the user becomes > connected again, system delivers the event notification to the user. > Base on my understanding, PUB/SUB does not define how to process > off-line event notification, is there any extension covering this > scenario? Any pointer is appreciated.
It is common for a user's server to save messages when a user is offline, so that when the user signs back on the server will send them. So I would say if you want this effect, it is the responsibility of the user's server to provide this feature. The pubsub service should not care about this. -Justin
