One possible reason I can think is for high availability. If Presence Server crashes and there is no high availability mechanism, the watcher will only know about this when it tries refreshing the subscription. Presence Server therefore may decrease the life time of subscription so that watcher can re-subscribe again once the subscription refresh fails and again establish the subscription.
The other reason is that Presence Server also needs to know whether UE that has subscribed is alive or not as there is no reason for it to have the subscription state for a UE that has crashed/stopped for a long time. On 5/28/07, Jeffrey <[EMAIL PROTECTED]> wrote: > > Hi all, > > I would like to know what consideration Presence Server acting as Notifier > wants to shorten the expiration time of presence event package subscription > requested from subscriber. Could you give me some reasons about this? If > subscribers request a subscription to Presence Server with long expiration > like 8 hours (28800 seconds) and Presence Server honors it, is there any > disadvantage caused? What consideration should Presence Server take into? > Thanks a lot. > > BR, > Jeffrey > > > > > %;+H%s%i/`%]'t$u,c0|>w1K8j0T!A+D+|)w$'&,%s*L!A=P$E(O%N)N4&ES%;+H%s$:.e!A(C=P>P74&9+H%s!C > This email may contain confidential information. Please do not use or > disclose it in any way and delete it if you are not the intended recipient. > _______________________________________________ > Sip-implementors mailing list > [email protected] > https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors > _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
