As the CANCEL was originated locally at the proxy,
487 would not be the right thing to send up to the callee
in this case. So given that:

choice1: terminate the INVITE transaction.
If the CANCEL worked and a 487 comes, it will not be forwarded.
If the CANCEL did not work, and 200 (for INV) will be forwarded
statelessly. If it comes to forwarding a response upstream, the proxy
will consider this scenario as 408 (timeout), which is good.

choice2: reset the timer and dont terminate
Will forward 200 OK if it comes - this is no gain as compared to (1).

I think choice 1 is good.

----- Original Message -----
From: "Sachin Shenoy" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Sunday, July 28, 2002 3:46 PM
Subject: [Sip-implementors] Timer C


> Hi,
>
> At Proxy, Consider a state where we have recieved 1xx for an
> INVITE that we sent out
>
> If now, Timer C fires,
>     1. Do we send out CANCEL and consider the INVITE as timed-out.
>     or
>     2. Do we send out CANCEL and wait for a proper response for the
INVITE.
>
> If it is (2), then would'nt it be better to restart timer C, after sending
out
> CANCEL. This is to ensure that we do clearup if INVITE is not responded
> anymore.
>
> (If the end-point which sent the 1xx crashed, it is not going to send us
> any response. Sending CANCEL to it and waiting is not going to help.)
>
> Hope I didn't miss anything over here?
>
> Thanks
> Sachin
>
> _______________________________________________
> Sip-implementors mailing list
> [EMAIL PROTECTED]
> http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
>

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