Hi,
Bit confused, but how does this help?
As I understand the answer for the offer in the 18x (identical SDP
repeated in the 200), will be answered only in the ACK to the 200 OK.
So what's the point in doing an "early offer" in an 18x, as the offer
answer can only be completed when the 200 OK/ACK exchange takes place.
Does sending an offer in 18x helps in any specific call flow?
Just curious...
Regards ,
Sayan
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Christer
Holmberg (JO/LMF)
Sent: Wednesday, February 16, 2005 4:11 AM
To: 'Paul Kyzivat'; Bala Neelakantan
Cc: [email protected]
Subject: RE: [Sip-implementors] SDP in 183 non reliable response
Hi,
To my understanding the same SDP shall be sent in all subsequent
provisional responses - no matter if they are sent reliably or not. You
can only have at most one offer/answer exchange per SIP transaction, so
once you've sent an offer (or answer, if the INVITE did contain an
offer) in 18x you can't send any more within that transaction.
When it comes to forking, each dialog is handled completely separate
from each other, ie the offer/answer "state" on one dialog is not
affected by other dialog. How the UAC then chooses which dialogs to
accept/reject, and how to handle possible media received from multiple
UASs, is an implementation issue.
Regards,
Christer Holmberg
Ericsson Finland
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] Behalf Of Paul
Kyzivat
Sent: 15. helmikuuta 2005 18:42
To: Bala Neelakantan
Cc: [email protected]
Subject: Re: [Sip-implementors] SDP in 183 non reliable response
Bala Neelakantan wrote:
Paul,
I agree that the same SDP should be sent in the subsequent
non-reliable
response and also on the first Reliable response.
I guess you are shifting from the subject of the original
question, and
discussing a "normal" invite that includes an offer.
What if the call is forked? In that case, there could be multiple
provisional responses, each could be potentially different?
How does the
UAC handle those?
This has been well documented and discussed, though it can
get complex.
The response to each fork creates a separate dialog. It is up
to the UAC
to keep the different dialogs straight until one is answered and the
others are cancelled.
Paul
Thanks,
Neel
-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf
Of Paul Kyzivat
Sent: Tuesday, February 15, 2005 9:48 AM
To: Steven Egan
Cc: [email protected]
Subject: Re: [Sip-implementors] SDP in 183 non reliable response
Well, I went back and read to refresh my memory. I agree
that there is
nothing that suggests SDP might be in an unreliable
provisional when
there had been no offer in the initial request.
If it *was* there, you wouldn't be able to consider it a
true offer,
since that must be in a reliable request or response. It
would have to
be a hint of the offer to come. I don't find any language that
explicitly *prohibits* this. But in the absence of anything
suggesting
it might be valid you would be best to not count on it.
Paul
Steven Egan wrote:
Hi Paul,
So you are saying that when an INVITE is sent with no
offer, a 183 with
SDP can be sent in response?
Can you point me to where exactly this is documented please, as my
problem is I cannot find anything in RFC 3261 or any other
documentation
to confirm expected behaviour for the 183?
Cheers,
Steven
Paul Kyzivat wrote:
Steven Egan wrote:
Hi,
Is it valid to include the SDP in a non reliable 183 sent
in response
to an Invite with no initial offer?
It is ok to include the SDP in the 183 when the Invite
contains the
initial offer, but RFC 3261 is not clear as to whether
the SDP can be
included when no offer is included in the initial invite.
I believe the answer is YES. The *same* SDP should be sent in the
first reliable response.
Paul
_______________________________________________
Sip-implementors mailing list
[email protected]
http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
_______________________________________________
Sip-implementors mailing list
[email protected]
http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
_______________________________________________
Sip-implementors mailing list
[email protected]
http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
Confidentiality Notice
The information contained in this electronic message and any attachments to
this message are intended
for the exclusive use of the addressee(s) and may contain confidential or
privileged information. If
you are not the intended recipient, please notify the sender at Wipro or [EMAIL
PROTECTED] immediately
and destroy all copies of this message and any attachments.
_______________________________________________
Sip-implementors mailing list
[email protected]
http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
