[Freeswitch-users] Fax Issues with Cisco SPA112 and T.38

Brian Foster bdfoster at endigotech.com
Wed May 16 06:10:22 MSD 2012


I think your problem is probably the fact that your FAX machine doesn't
support t.38. In that case you'd have to have freeswitch transcode from
pcmu to t.38. It doesn't give good results when your server isn't on the
LAN that your ATA is on. The point really of transmitting to flowroute as
t.38 is to get better results when transmitting a FAX via VoIP. You would
essentially be taking a detour to get a transcode and it really doesn't
help because like I said your server is somewhere out in cyberspace. Also
mix in that it is indeed a VPS, and that's pro ably what you are seeing the
result of. Maybe the Atari actually transcodes to t.38 locally, I'm not
sure and I don't have enough experience with that device to be able to tell
you. If the ATA is indeed locally trandcoding to t.38 then my suggestion
would be to bypass media on the server and sent it straight to flowroute.

I hope this helps. If you have any questions let us know!

-BDF
On May 15, 2012 6:52 PM, "Chris Ferreira" <chris at gonumina.com> wrote:

> Hello Brian and Everyone,
>
>
> Here is a link to the siptrace output. Sorry for the delay, it was my
> birthday and I was away for the weekend.
>
>
> http://pastebin.freeswitch.org/19057
>
>
> Thanks,
>
> -Chris
>
>
>
>
> On Thu, May 10, 2012 at 10:16 PM, Brian Foster <bdfoster at endigotech.com>wrote:
>
>> 1. Run fs_cli and do 'sofia global siptrace on' without quotes. Stay in
>> the cli and run a call in an instance where it would fail. Make sure your
>> scroll buffer on your SSH terminal (PuTTY or what ever you have) to
>> unlimited or something bog like 20K lines. Copy the logs out and put them
>> on http://pastebin.freeswitch.org. If prompted for a username/password,
>> please read the dialog box. SpanDSP doesn't have a great ability to be
>> degugged on the click but it will give is something to go on.
>>
>> 2. There usually isn't much you can do as far as ensuring the VPS is
>> capable of keeping the timing right. VoIP is reliant heavily on a good
>> timing source. Faxing is even more dependent.
>>
>> I'm not really sure what the MOS score is useful for, maybe someone else
>> can chime in on that.
>>
>> Something you need to make sure you are doing (specifically with
>> flowroute) is making sure you are doing a t.38 reinvite. Flowroute does not
>> auto detect t.38. Also freeswitch might have to transcode from audio
>> ulaw/alaw to t.38 if your FAX machine doesn't actually support t.38.
>>
>> I don't really know much about the new SPA 112/122's but usually the ATA
>> has a t.38 passthru mode that is auto detected. That might be what you are
>> referring to.
>>
>> -BDF
>> On May 10, 2012 2:35 PM, "Chris Ferreira" <chris at gonumina.com> wrote:
>>
>>> Hi Bryan,
>>>
>>>
>>> Thanks for your response, much appreciated.
>>>
>>>
>>> 1. I have never had to do a debug other than analyze fs_cli output and
>>> iv'e never done a sip trace. I have started reading up on how to do these
>>> on the Wiki and will generate some files to take a look at.
>>>
>>>
>>> 2. I have heard this before about VPS's and even VMWare servers running
>>> on local physical hardware. I hope to be able to overcome these issues.
>>>
>>>
>>> 3. Other calls work fine throughout the switch and between carriers.
>>>
>>>
>>>
>>> I don't know if this is a good actual measure of anything, but
>>> VoIPSpear.com says that the servers MOS Score is a 4.0 .
>>>
>>>
>>> Other than the server running on a VPS, is my setup with the ATA
>>> registering to FreeSWITCH as an intermediary between Flowroute.com a
>>> correct practice? Or is there something else I could be doing?
>>>
>>>
>>> I know that if I was not needing to use an Analog Fax machine for
>>> sending/receiving that I would have other options. But unfortunately the
>>> Dinosaur must have it's Dial Tone.
>>>
>>>
>>>
>>> Thanks,
>>>
>>> -Chris
>>>
>>>
>>>
>>>
>>> On Thu, May 10, 2012 at 2:03 PM, Brian Foster <bdfoster at endigotech.com>wrote:
>>>
>>>> 1. Debug tells all. We need the siptrace as well.
>>>>
>>>> 2. VPS's are usually bad at sending/receiving faxes even if the media
>>>> is just being routed through it.
>>>>
>>>> 3. You could also look at session timers. Are other calls working?
>>>>
>>>> The only real way to know is if we have number 1 in our possession,
>>>> otherwise we just start guessing.
>>>>
>>>> -BDF
>>>>
>>>> On Thu, May 10, 2012 at 1:30 PM, Chris Ferreira <chris at gonumina.com>wrote:
>>>>
>>>>> Hello All,
>>>>>
>>>>>
>>>>>
>>>>> I have a FreeSWITCH install running on CentOS 5.6 on a Linode VPS. I
>>>>> am trying to get my SPA112 (Version 1.1 Firmware) to send faxes (and
>>>>> eventually receive) successfully. I have the ATA registered as an extension
>>>>> and it's primary outgoing route is through Flowroute. I have T.38 enabled
>>>>> on the ATA and I have diabled ECM on the analog fax machine. All of the
>>>>> CDR's in Flowroute show that the test faxes are all ending their calls at
>>>>> 39 seconds.
>>>>>
>>>>>
>>>>> I can post screen shots of the ATA config or provide any other config
>>>>> info.
>>>>>
>>>>>
>>>>> Is there something I am missing, or should this setup work?
>>>>>
>>>>> I have poked around for a while for info, but unlike the PAP2T there
>>>>> is little info on these SPA112's. This is my first post asking for help as
>>>>> I usually try to resolve things on my own. But for this, I will defer
>>>>> to everyone's experience.
>>>>>
>>>>>
>>>>>
>>>>> Thanks,
>>>>>
>>>>> -Chris
>>>>>
>>>>>
>>>>> _________________________________________________________________________
>>>>> Professional FreeSWITCH Consulting Services:
>>>>> consulting at freeswitch.org
>>>>> http://www.freeswitchsolutions.com
>>>>>
>>>>> 
>>>>> 
>>>>>
>>>>> Official FreeSWITCH Sites
>>>>> http://www.freeswitch.org
>>>>> http://wiki.freeswitch.org
>>>>> http://www.cluecon.com
>>>>>
>>>>> FreeSWITCH-users mailing list
>>>>> FreeSWITCH-users at lists.freeswitch.org
>>>>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
>>>>> UNSUBSCRIBE:
>>>>> http://lists.freeswitch.org/mailman/options/freeswitch-users
>>>>> http://www.freeswitch.org
>>>>>
>>>>>
>>>>
>>>>
>>>> --
>>>> Brian D. Foster
>>>> Endigo Computer LLC
>>>> Email: bdfoster at endigotech.com
>>>> Phone: 317-800-7876
>>>> Indianapolis, Indiana, USA
>>>>
>>>> This message contains confidential information and is intended for
>>>> those listed in the "To:", "CC:", and/or "BCC:" fields of the message
>>>> header. If you are not the intended recipient you are notified that
>>>> disclosing, copying, distributing or taking any action in reliance on the
>>>> contents of this information is strictly prohibited. E-mail transmission
>>>> cannot be guaranteed to be secure or error-free as information could be
>>>> intercepted, corrupted, lost, destroyed, arrive late or incomplete, or
>>>> contain viruses. The sender therefore does not accept liability for any
>>>> errors or omissions in the contents of this message, which arise as a
>>>> result of e-mail transmission. If verification is required please request a
>>>> hard-copy version.
>>>>
>>>>
>>>>
>>>> _________________________________________________________________________
>>>> Professional FreeSWITCH Consulting Services:
>>>> consulting at freeswitch.org
>>>> http://www.freeswitchsolutions.com
>>>>
>>>> 
>>>> 
>>>>
>>>> Official FreeSWITCH Sites
>>>> http://www.freeswitch.org
>>>> http://wiki.freeswitch.org
>>>> http://www.cluecon.com
>>>>
>>>> FreeSWITCH-users mailing list
>>>> FreeSWITCH-users at lists.freeswitch.org
>>>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
>>>> UNSUBSCRIBE:
>>>> http://lists.freeswitch.org/mailman/options/freeswitch-users
>>>> http://www.freeswitch.org
>>>>
>>>>
>>>
>>> _________________________________________________________________________
>>> Professional FreeSWITCH Consulting Services:
>>> consulting at freeswitch.org
>>> http://www.freeswitchsolutions.com
>>>
>>> 
>>> 
>>>
>>> Official FreeSWITCH Sites
>>> http://www.freeswitch.org
>>> http://wiki.freeswitch.org
>>> http://www.cluecon.com
>>>
>>> FreeSWITCH-users mailing list
>>> FreeSWITCH-users at lists.freeswitch.org
>>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
>>> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
>>> http://www.freeswitch.org
>>>
>>>
>> _________________________________________________________________________
>> Professional FreeSWITCH Consulting Services:
>> consulting at freeswitch.org
>> http://www.freeswitchsolutions.com
>>
>> 
>> 
>>
>> Official FreeSWITCH Sites
>> http://www.freeswitch.org
>> http://wiki.freeswitch.org
>> http://www.cluecon.com
>>
>> FreeSWITCH-users mailing list
>> FreeSWITCH-users at lists.freeswitch.org
>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
>> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
>> http://www.freeswitch.org
>>
>>
>
> _________________________________________________________________________
> Professional FreeSWITCH Consulting Services:
> consulting at freeswitch.org
> http://www.freeswitchsolutions.com
>
> 
> 
>
> Official FreeSWITCH Sites
> http://www.freeswitch.org
> http://wiki.freeswitch.org
> http://www.cluecon.com
>
> FreeSWITCH-users mailing list
> FreeSWITCH-users at lists.freeswitch.org
> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
> http://www.freeswitch.org
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20120515/349d0ce7/attachment-0001.html 


Join us at ClueCon 2011 Aug 9-11, 2011
More information about the FreeSWITCH-users mailing list