> As per the below description, AS has to send NOTIFY > and Core network has to reject it in order to cancel > the subscription.
Those are not the only ways to terminate the subscription. If the NOTIFY is to terminate the subscription, the transferor does not have to reject the NOTIFY. If the NOTIFY is not to terminate the subscription, the transferor can 1) reject the NOTIFY or 2) send a re-SUBSCRIBE to terminate the subscription. Number 2 appears to be preferred by RFC 3515; although it does indicate the potential for number 1. RFC 4488 also provides a mechanism to avoid sending/receiving a useless NOTIFY. > If AS sends a BYE Message directly without NOTIFY, > whether subscription will be deleted? If No, How long > the subscription in Core Network will be active? Draft-ietf-sipcore-rfc3265bis-02 defined Timer N for use when awaiting the expected NOTIFY. Timer N defaults to 64*T1. However if the transferor plans to reject the NOTIFY, the transferor typically does not need to really maintain subscription state (especially after the call dialog usage has been released) unless using such knowledge to produce a better NOTIFY response. _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
