On Fri, 2009-01-23 at 18:59 +0200, Andrew Pogrebennyk wrote: > It may be no good for long-living subscriptions found in such services > as BLF if the application removes the subscription after failed > non-immediate NOTIFY. It means that brief network or systems > malfunctioning can disrupt the service. OTOH, NOTIFYs are sent on the > same dialog and I'm not sure we could tolerate the error response and > keep the dialog active.
Yes, it's a significant problem in practice. In the next release of the sipX open-source stack, we're amending the notifier behavior to not delete a subscription when a NOTIFY receives an error response. We expect that to significantly improve the performance of BLF on phones. > I guess that if failed non-immediate NOTIFY should be considered the > reason for subscription termination, it's particularly important that > notifier sends, as per RFC, a NOTIFY message with a "Subscription-State" > value of "terminated" to inform it that the subscriber that subscription > is being removed. Please let me know your thoughts. Thanks, If the non-immediate NOTIFY gets a 408, then immediately sending a second NOTIFY isn't going to make a difference. Dale _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
