Hi Dale,
You mean to say that I should reply to the NOTIFY with 200Ok but this
NOTIFY is not going to effect the already agreed upon expire value of
250. So, their can never be an error scenario with respect to Subscribe
duration, as such mismatch can happen anytime, Right..? I was actually
thinking it to be an error case, responding with 4xx (may be 488) or
terminate the dialog and send a fresh subscribe.
Any clarification will be helpful.
Regards
Ajit


-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of
[EMAIL PROTECTED]
Sent: Tuesday, November 28, 2006 1:19 AM
To: [email protected]
Subject: Re: [Sip-implementors] Calculation of Subscribe Duration

   From: "Ajit Kumar" <[EMAIL PROTECTED]>

   Suppose I am already having an established SUBSCRIBE dialog and the
   subscription expires after 700sec. Now, I am doing a Re-Subscribe to
   refresh my Subscription with a lesser value say 300sec. The Notifier
   sends 200ok for the re-subscribe with Expires 250 say. Now I have set
my
   expiry to be 250sec. After getting the 200Ok for Re-Subscribe I got a
   Notify which suggests Expires to be 400sec, this notify can be the
   delayed Notify of my previous subscription which was supposed to
expire
   after 700sec. Now, how I should respond to this Notify, as my current
   expires is 250 and what I am getting is exceeding the value I
proposed
   in Re-Subscribe.

It's a messy problem.  There was a discussion on the SIP mailing list
a month or so ago, but I'm so far behind on my e-mail, I don't know if
a consensus was reached.

At one point, I advocated that once a subscription endpoint was
established, both the Subscriber and the Notifier would be constrained
to only push the endpoint further into the future (except when
terminating the subscription immediately).  That eliminates many
ambiguities.

In the specific case you describe:

Clearly, you should respond 200 to the NOTIFY.

Because the NOTIFY was likely sent by the Notifier before the
re-subscribe, the Subscriber should retain the earlier subscription
endpoint (250 secs.), which was agreed upon after the later
subscription endpoint.

This policy is safe...

Dale
_______________________________________________
Sip-implementors mailing list
[email protected]
https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors

The information contained in this message may be confidential to Kodiak 
Networks, Inc. and its subsidiaries and protected from disclosure. If this 
message did not reach the intended recipient, or an employee or agent 
responsible for delivering it to the intended recipient, you are hereby 
informed that any distribution or copying of this communication is prohibited. 
If you have received this communication in error, please notify us immediately 
by replying to the sender of the message and then delete the message. Thank you.

_______________________________________________
Sip-implementors mailing list
[email protected]
https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors

Reply via email to