Hi

Could someone explain the correct transition for a subscription in 
Active state when the sub-handling permision changes to Confirm?

According to RFC 3857, the only allowed transition from Active state is 
to the Terminated state.  However, the Presence Authorization Rules 
document 
(http://www.potaroo.net/ietf/idref/draft-ietf-simple-presence-rules) states:
"If the sub-handling permission changes value to confirm, the processing 
depends on the states of the affected subscriptions. Unfortunately, the 
state machine in RFC 3857 does not define an event corresponding to an 
authorization decision of "pending".  If the subscription is in the 
active state, it moves back into the pending state. This causes a NOTIFY 
to be sent, updating the Subscription-State [7] to "pending".  No reason 
is included in the Subscription-State header field (none are defined to 
handle this case).  No further documents are sent to this watcher."

That is, RFC 3857 seems to requre a transition to Terminated state, 
while the Presence Authorization Rules mandates a transition to Pending 
state.

In the latter case, the problem is that a transition to Pending state 
causes unexpected behavior when the subscription is termiated 
(SUBSCRIPTION with Expire set to 0).  RFC 3857 would require the 
subscription to transition into Waiting state and fire a Watcher Info 
NOTIFY with Subsription-State header set to Waiting.  This would in turn 
trigger a confirmation dialog to the subscribed user about the seemingly 
"waiting" subscription ... which is totaly unexpected, since the watcher 
in fact did an unsubscribe.


Best regards,
Per-Ivar

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