Subject: [sipcore] draft-ietf-sipcore-reinvite-04: 4xx and UPDATE from UAS

From: OKUMURA Shinji <[email-masked]>
Date: Mon, 07 Jun 2010 12:56:29 +0900

Hi all,

In following cases, should a UAC(A) send a new offer to sync
a common view?

    A                               B
    |                               |
  s0|re-INV (offer1)                |s0
    |------------------------------>|
    |               18x-rel(answer1)|
    |<------------------------------|
  s1|                        non-2xx|s1
    |<------------------------------|
  s0|ACK               ACK          |s0
    |------------>     ------------>|
    |                    UPD(offer2)|
    |<==============================|
    |2xx-UPD(answer2)               |
    |==============================>|
  s2|                               |s2
    |                               |

    A                               B
    |                               |
  s0|re-INV (offer1)                |s0
    |------------------------------>|
    |               18x-rel(answer1)|
    |<------------------------------|
  s1|                    UPD(offer2)|s1
    |                  /============|
    |                 /      non-2xx|
    |<---------------/--------------|
  s0|ACK            /   ACK         |s0
    |------------> /    ----------->|
    |             /                 |
    |<===========/                  |
    |2xx-UPD(answer2)               |
    |==============================>|
  s2|                               |s2
    |                               |

I think a common view of both UAs has been already synchronized.

Regards,
Shinji