LobsterMonster.org

I ended up with a problem to keep a track if the anonymous users communicating with me using the contact pages were still online or not.

I first tried to handle this problem by sending direct presence from the "anonymous-web-user" to my IM client but it ended up not to be the best practice due 2 problems; Kopete and Psi do not show the presence of anonymous contacts correctly (at least not for me @ 2009-05-02). Secondly it's up to the anonymous connection in this "direct presence case" to send the final unavailable -presence. Since the anonymous connection on the contact pages is implemented using BOSH, the unavailable -presence could not arrive/never be send due multiple reasons.

So I ended up implementing XEP-0199: XMPP Ping. Now, if I'm in doubt if the contact is still online or not, using my IM client I can ping the anonymous user. It's not the best practice but at least it makes the system more usable.