Please see my comments/questions below...

  Tolga

[..snip..]
> Here is the essence of what's causing us to have this conversation
> I think. How can you be in a state where a watcher has sufficient
> authorization for a subscription to enter the active state and have
> the refresh SUBSCRIBE _NOT_ be approved? The only way I can think of
> is if the presentity has removed approval, in which case the
> subscription is no longer active.
[TOLGA] Yes, I also believe this is the crucial point. Let's assume my
initial subscribe has expiry timer of 100s. And it is authorized. At t=50s ,
I sent SUBSCRIBE2 (with Expires=100s). Let's assume, notifier can't decide
immediately, whether I am approved for subscriptions more than 100s - I
don't think this is unrealistic, subscribing for a resouce/entity for more
than a certain amount of time might require additional authorization-.
Subscriber has still have the authorized 50s from intial SUBSCRIBE. Now,
notifier can send 200(SUBSCRIBE, Expires=50s) and NOTIFY(active) -50s is,
what is left from the initial subscribe, nothing new approved yet, and
because subscription is active -conclusion based on this thread till now,
always use current subscription state-, Subscription-State=active in NOTIFY,
this also means that the original scenario I did draw was not just odd, but
also wrong, i.e. it shouldn't be valid from protocol point of view and a
refreshing SUBSCRIBE should never be answered with NOTIFY(pending)). After a
while, notifier decides to approve SUBSCRIBE2. How can it inform subscriber
about this? Sending a new NOTIFY(active) and using "expires" parameter? I
believe, there is nothing not allowing to do so in RFC3265 but I doubt,
whether majority of implemantations would behave properly in such a case,
i.e. updating subscription timer based on "expires" field in such a
NOTIFY(active), which was not sent directly as response to a reSUBSCRIBE.

[..snip..]

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