[SIPForum-discussion] simultaneous INVITEs

[Deepanshu]

inline
----- Original Message -----
From: "Niklas Fondberg" <niklas.fondberg at tilgin.com>
To: <discussion at sipforum.org>
Sent: Tuesday, March 27, 2007 3:30 AM
Subject: [SIPForum-discussion] simultaneous INVITEs


> Hi,
> I new to this list but I hope that the list is what I'm after; an
> implementation and design discussion list about SIP.
> If my question is wrongly addressed, please forgive me and please point
> me the right direction...
>
> My question that I have searched all over for an answer to is quite
> simple:
>
> What is the correct behavior for a UA if a second INVITE arrives before
> the first has been answered?
>
> SIP Flow:
>
> -------------> INVITE (1)
> <------------- 100 Trying (1)
> <------------- 180 Ringing (1)
> -------------> INVITE (2)
> ... ???
>
> Here the first (1) INVITE could have been answered by some other UA that
> the INVITE might have been forked to and in this case session (2) should
> start ringing.

If the first (1) INVITE could have been answered by some other UA then the
originating UAC SHALL send a CANCEL request towards UAS instead of a INVITE
(2).

-------------> INVITE (1)
<------------- 100 Trying (1)
<------------- 180 Ringing (1)
--------------> CANCEL (1)
                        stop ringing
<------------- SIP 487 (1)


HTH

Deepanshu Gautam
R&D Engineer
Huawei Technologies Co. Ltd.
Nanjing, PRC

>
>
> Niklas Fondberg
>
>
>
> _______________________________________________
> This is the SIP Forum discussion mailing list
> TO UNSUBSCRIBE, or edit your delivery options, please visit
http://sipforum.org/mailman/listinfo/discussion
> Post to the list at discussion at sipforum.org
>