It isn't entirely clear what the fundamental question is.
The original question seems to be concerned with whether it is allowed
to go back to audio after having previously switched to fax. But this is
mixed up with details of the SDP involved.
IIUC, the scenario involves *3* O/A exchanges:
(
Hi,
The 3rd SDP is illegal.
RFC3264
8 Modifying the Session
If an SDP is offered, which is different from the previous SDP, the
new SDP MUST have a matching media stream for each media stream in
the previous SDP. In other words, if the previous SDP had N "m="
lines, the new SDP MUST
Hello,
On 2015-07-31 10:05, Tarun2 Gupta wrote:
Hi Nitin
This is a perfectly legal scenario, the 2nd ReINVITE is essentially a Stop Fax
/ Revert to Audio ReINVITE.
We have seen this behavior with many T.38 vendors.
Quite probably, but this does not make it legal. In the last re-INVITE
the
Hi Tarun,
Thanks for answer. Can you please advise of there is any document we have
Where i can do some study/research?
Regards
Nitin
On 00:05, Fri, Jul 31, 2015 Tarun2 Gupta wrote:
> Hi Nitin
>
> This is a perfectly legal scenario, the 2nd ReINVITE is essentially a Stop
> Fax / Revert to Audi
Hi Nitin
This is a perfectly legal scenario, the 2nd ReINVITE is essentially a Stop Fax
/ Revert to Audio ReINVITE.
We have seen this behavior with many T.38 vendors.
Regards
Tarun Gupta
-Original Message-
From: sip-implementors-boun...@lists.cs.columbia.edu
[mailto:sip-implementors-
Hi Puneet,
Below is the SDP for Fax Re-invite from Vendor (UAS) after audio call
established with initial offer.
*T.38 RE INVITE SDP*
v=0
o=HuaweiSoftX3000 32970986 32970988 IN IP4 1.1.1.1
s=Sip Call
c=IN IP4 1.1.1.1
t=0 0
m=image 41046 udptl t38
a=T38FaxVersion:0
a=T38MaxBitRate:14400
a=T38Fax
