[OpenSIPS-Users] Prevent re-INVITE to T.38

[Jeff Pyle]

Hi Ovidiu,

In the case of a pure T.38 SDP offer like this:

v=0
o=- 1394560461 1394560461 IN IP4 192.168.58.4
s=-
c=IN IP4 192.168.58.4
t=0 0
m=image 16426 udptl t38
a=T38FaxVersion:0
a=T38FaxRateManagement:transferredTCF
a=T38FaxFillBitRemoval:0
a=T38FaxTranscodingMMR:0
a=T38FaxTranscodingJBIG:0
a=T38MaxBitRate:14400
a=T38FaxUdpEC:t38UDPRedundancy
a=T38FaxMaxBuffer:600
a=T38FaxMaxDatagram:200


Which codec would I remove?


- Jeff



On Tue, Mar 11, 2014 at 1:44 PM, Ovidiu Sas <osas at voipembedded.com> wrote:

> Remove the codec and let the re-INVITE go through.
>
> Regards,
> Ovidiu Sas
>
>
>
> On Tue, Mar 11, 2014 at 1:42 PM, Jeff Pyle <jpyle at fidelityvoice.com>wrote:
>
>> Hi Alexander,
>>
>> To detect the "image" session in the SDP, you are thinking the same way
>> that I am.  The problem I see is how to actually reject the re-INVITE.  If
>> I were to do something like a sl_send_reply("488", "Not Acceptable Here"),
>> that would work in the moment, but the CSeq values would be increased by
>> one on side compared to the other.  That sounds to me like a recipe for
>> problems in future in-dialog transactions (like BYE).
>>
>>
>>
>> - Jeff
>>
>>
>>
>>
>> On Tue, Mar 11, 2014 at 12:58 PM, Alexander Mustafin <
>> mustafin.aleksandr at gmail.com> wrote:
>>
>>> Hi, Jeff.
>>>
>>> Maybe stream_exists(regexp) in sipmsgops module will be useful for you.
>>>
>>>  Best regards,
>>> Alexander Mustafin
>>> mustafin.aleksandr at gmail.com
>>>
>>>
>>>
>>>
>>> 11 марта 2014 г., в 20:07, Jeff Pyle <jpyle at fidelityvoice.com>
>>> написал(а):
>>>
>>> Hello,
>>>
>>> Is there anything I can do at the proxy level to prevent a dialog from
>>> reinviting to to T.38?  I think I could detect the T.38 attributes easily
>>> enough and respond with a 488, although I'm concerned the CSeq values would
>>> be out of sequence for the next transaction that did make it through the
>>> proxy to the far end.  That could cause a problem, no?
>>>
>>> Is this something that requires a B2BUA?  Is it possible from within the
>>> OpenSIPS B2B modules to do SDP inspection of any sort?
>>>
>>>
>>> - Jeff
>>>
>>>  _______________________________________________
>>> Users mailing list
>>> Users at lists.opensips.org
>>> http://lists.opensips.org/cgi-bin/mailman/listinfo/users
>>>
>>>
>>>
>>> _______________________________________________
>>> Users mailing list
>>> Users at lists.opensips.org
>>> http://lists.opensips.org/cgi-bin/mailman/listinfo/users
>>>
>>>
>>
>> _______________________________________________
>> Users mailing list
>> Users at lists.opensips.org
>> http://lists.opensips.org/cgi-bin/mailman/listinfo/users
>>
>>
>
>
> --
> VoIP Embedded, Inc.
> http://www.voipembedded.com
>
> _______________________________________________
> Users mailing list
> Users at lists.opensips.org
> http://lists.opensips.org/cgi-bin/mailman/listinfo/users
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.opensips.org/pipermail/users/attachments/20140311/f8cacca1/attachment-0001.htm>