[Freeswitch-users] T.38 three re-invites then bye

Thu Aug 23 19:15:07 MSD 2012

You could hack the sdp in your dialplan by getting the variable and
re-setting it but I am not sure if that would work or not.
Otherwise you could try a proxy.

On Thu, Aug 23, 2012 at 10:08 AM, Leon de Rooij
<leon at scarlet-internet.nl> wrote:
> Hi all,
>
> I've been having a problem with a new provider with sending them faxes over T.38. I don't think FreeSWITCH is to blame at all, but maybe FS can fix my issue, or someone here can help me find the cause of the problem ?
>
> The call flow is as follows:
>
> CPE
> 1.1.1.1
>      |
>     V
> 2.2.2.2
> FreeSWITCH
> 3.3.3.3
>      |
>     V
> 4.4.4.4
> Provider
>
> In FreeSWITCH, I've set t38-passthru to true on the profile where the CPE INVITEs to. Further, I'm doing late negotiation (while offering the a-leg codecs to the b-leg and the other way around). RTP is flowing through FS.
>
> In short, this is happening:
>
> CPE -> FS -> Provider           INVITE (with audio PCMA, PCMU codecs)
> Provider -> FS -> CPE           200 OK (with audio PCMA)
>
> CPE -> FS -> Provider           reINVITE (with T.38 in SDP)
> Provider -> FS -> CPE           200 OK (with T.38 in SDP - although with different error correction, is this a problem?)
>
> Provider -> FS -> CPE           reINVITE (again with T.38 in SDP)
> CPE -> FS -> Provider           200 OK (with T.38 in SDP)
>
> CPE -> FS -> Provider           reINVITE (with T.38 in SDP)
> Provider -> FS -> CPE           BYE (of course, or it'll loop forever)
>
> Does a setting in FreeSWITCH exist so that it can change the error correction (because both endpoints seem to want a different one ?) Could that be the cause of the problem ?
>
> Hope anyone can help.
>
> Thanks,
>
> Leon
>
>
>
>
>
> Here's the trace - I left out the tryings, acks, removed some unnecessary sip headers to make things a bit less verbose:
>
>
> U 2012/08/23 15:34:16.334938 3.3.3.3:5060 -> 4.4.4.4:5060
> INVITE sip:+888 at 4.4.4.4 SIP/2.0.
> From: "+777" <sip:+777 at provider.voip.tel>;tag=70aprjj2Z1QKK.
> To: <sip:+888 at 4.4.4.4>.
> Call-ID: 3bf65bb6-ed27-11e1-a810-1d8ba1d695aa.
> CSeq: 32528364 INVITE.
> Contact: <sip:gw+provider-voip-tel at 3.3.3.3:5060;transport=udp;gw=provider-voip-tel>.
> Content-Type: application/sdp.
> Content-Disposition: session.
> Content-Length: 253.
> X-Designated-Service: fax/t38.
> .
> v=0.
> o=FreeSWITCH 1345708964 1345708965 IN IP4 3.3.3.3.
> s=FreeSWITCH.
> c=IN IP4 3.3.3.3.
> t=0 0.
> m=audio 19892 RTP/AVP 8 0 101 13.
> a=rtpmap:8 PCMA/8000.
> a=rtpmap:0 PCMU/8000.
> a=rtpmap:101 telephone-event/8000.
> a=fmtp:101 0-16.
> a=ptime:30.
>
>
> U 2012/08/23 15:34:18.192303 4.4.4.4:5060 -> 3.3.3.3:5060
> SIP/2.0 180 Ringing.
> From: "+777" <sip:+777 at provider.voip.tel>;tag=70aprjj2Z1QKK.
> To: <sip:+888 at 4.4.4.4>;tag=SDkvc5299-1.45.133.551104+1+a1b50004+4166b8ad.
> Call-ID: 3bf65bb6-ed27-11e1-a810-1d8ba1d695aa.
> CSeq: 32528364 INVITE.
> Server: DC-SIP/2.0.
> Content-Length: 0.
> Contact: <sip:+888 at 4.4.4.4:5060;transport=udp>.
> .
>
>
> U 2012/08/23 15:34:23.904745 4.4.4.4:5060 -> 3.3.3.3:5060
> SIP/2.0 200 OK.
> From: "+777" <sip:+777 at provider.voip.tel>;tag=70aprjj2Z1QKK.
> To: <sip:+888 at 4.4.4.4>;tag=SDkvc5299-1.45.133.551104+1+a1b50004+4166b8ad.
> Call-ID: 3bf65bb6-ed27-11e1-a810-1d8ba1d695aa.
> CSeq: 32528364 INVITE.
> Server: DC-SIP/2.0.
> Contact: <sip:+888 at 4.4.4.4:5060;transport=udp>.
> Content-Type: application/sdp.
> Content-Length: 229.
> .
> v=0.
> o=- 3554717663 3554717663 IN IP4 4.4.4.4.
> s=-.
> c=IN IP4 4.4.4.4.
> t=0 0.
> m=audio 22054 RTP/AVP 8 101.
> a=ptime:30.
> a=rtpmap:8 PCMA/8000.
> a=rtpmap:101 telephone-event/8000.
> a=fmtp:101 0-15.
> a=silenceSupp:off - - - -.
>
>
> U 2012/08/23 15:34:23.996849 3.3.3.3:5060 -> 4.4.4.4:5060
> INVITE sip:+888 at 4.4.4.4:5060;transport=udp SIP/2.0.
> From: "+777" <sip:+777 at provider.voip.tel>;tag=70aprjj2Z1QKK.
> To: <sip:+888 at 4.4.4.4>;tag=SDkvc5299-1.45.133.551104+1+a1b50004+4166b8ad.
> Call-ID: 3bf65bb6-ed27-11e1-a810-1d8ba1d695aa.
> CSeq: 32528365 INVITE.
> Contact: <sip:gw+provider-voip-tel at 3.3.3.3:5060;transport=udp;gw=provider-voip-tel>.
> Content-Type: application/sdp.
> Content-Disposition: session.
> Content-Length: 339.
> X-Designated-Service: fax/t38.
> .
> v=0.
> o=FreeSWITCH 1345708964 1345708966 IN IP4 3.3.3.3.
> s=FreeSWITCH.
> c=IN IP4 3.3.3.3.
> t=0 0.
> m=image 19892 udptl t38.
> a=T38FaxVersion:0.
> a=T38MaxBitRate:14400.
> a=T38FaxTranscodingMMR.
> a=T38FaxTranscodingJBIG.
> a=T38FaxRateManagement:transferredTCF.
> a=T38FaxMaxBuffer:500.
> a=T38FaxMaxDatagram:512.
> a=T38FaxUdpEC:t38UDPFEC.
>
>
> U 2012/08/23 15:34:24.093598 4.4.4.4:5060 -> 3.3.3.3:5060
> SIP/2.0 200 OK.
> From: "+777" <sip:+777 at provider.voip.tel>;tag=70aprjj2Z1QKK.
> To: <sip:+888 at 4.4.4.4>;tag=SDkvc5299-1.45.133.551104+1+a1b50004+4166b8ad.
> Call-ID: 3bf65bb6-ed27-11e1-a810-1d8ba1d695aa.
> CSeq: 32528365 INVITE.
> Server: DC-SIP/2.0.
> Contact: <sip:+888 at 4.4.4.4:5060;transport=udp>.
> Content-Type: application/sdp.
> Content-Length: 272.
> .
> v=0.
> o=- 3554717663 3554717664 IN IP4 4.4.4.4.
> s=-.
> c=IN IP4 4.4.4.4.
> t=0 0.
> m=image 22054 udptl t38.
> a=T38FaxVersion:0.
> a=T38MaxBitRate:14400.
> a=T38FaxRateManagement:transferredTCF.
> a=T38FaxMaxBuffer:72.
> a=T38FaxMaxDatagram:316.
> a=T38FaxUdpEC:t38UDPRedundancy.
>
>
> U 2012/08/23 15:34:33.885255 4.4.4.4:5060 -> 3.3.3.3:5060
> INVITE sip:gw+provider-voip-tel at 3.3.3.3:5060;transport=udp;gw=provider-voip-tel SIP/2.0.
> Call-ID: 3bf65bb6-ed27-11e1-a810-1d8ba1d695aa.
> From: <sip:+888 at 4.4.4.4>;tag=SDkvc5299-1.45.133.551104+1+a1b50004+4166b8ad.
> To: "+777" <sip:+777 at provider.voip.tel>;tag=70aprjj2Z1QKK.
> CSeq: 693734809 INVITE.
> Contact: <sip:+888 at 4.4.4.4:5060;transport=udp>.
> Content-Type: application/sdp.
> Content-Length: 272.
> .
> v=0.
> o=- 3554717663 3554717665 IN IP4 4.4.4.4.
> s=-.
> c=IN IP4 4.4.4.4.
> t=0 0.
> m=image 22054 udptl t38.
> a=T38FaxVersion:0.
> a=T38MaxBitRate:14400.
> a=T38FaxRateManagement:transferredTCF.
> a=T38FaxMaxBuffer:72.
> a=T38FaxMaxDatagram:316.
> a=T38FaxUdpEC:t38UDPRedundancy.
>
>
> U 2012/08/23 15:34:33.939092 3.3.3.3:5060 -> 4.4.4.4:5060
> SIP/2.0 200 OK.
> From: <sip:+888 at 4.4.4.4>;tag=SDkvc5299-1.45.133.551104+1+a1b50004+4166b8ad.
> To: "+777" <sip:+777 at provider.voip.tel>;tag=70aprjj2Z1QKK.
> Call-ID: 3bf65bb6-ed27-11e1-a810-1d8ba1d695aa.
> CSeq: 693734809 INVITE.
> Contact: <sip:gw+provider-voip-tel at 3.3.3.3:5060;transport=udp;gw=provider-voip-tel>.
> Accept: application/sdp.
> Content-Type: application/sdp.
> Content-Disposition: session.
> Content-Length: 345.
> .
> v=0.
> o=FreeSWITCH 1345708964 1345708967 IN IP4 3.3.3.3.
> s=FreeSWITCH.
> c=IN IP4 3.3.3.3.
> t=0 0.
> m=image 19892 udptl t38.
> a=T38FaxVersion:0.
> a=T38MaxBitRate:14400.
> a=T38FaxTranscodingMMR.
> a=T38FaxTranscodingJBIG.
> a=T38FaxRateManagement:transferredTCF.
> a=T38FaxMaxBuffer:72.
> a=T38FaxMaxDatagram:512.
> a=T38FaxUdpEC:t38UDPRedundancy.
>
>
> U 2012/08/23 15:34:33.950201 3.3.3.3:5060 -> 4.4.4.4:5060
> INVITE sip:+888 at 4.4.4.4:5060;transport=udp SIP/2.0.
> From: "+777" <sip:+777 at provider.voip.tel>;tag=70aprjj2Z1QKK.
> To: <sip:+888 at 4.4.4.4>;tag=SDkvc5299-1.45.133.551104+1+a1b50004+4166b8ad.
> Call-ID: 3bf65bb6-ed27-11e1-a810-1d8ba1d695aa.
> CSeq: 32528366 INVITE.
> Contact: <sip:gw+provider-voip-tel at 3.3.3.3:5060;transport=udp;gw=provider-voip-tel>.
> User-Agent: c4-provider-ims-intx.
> Content-Type: application/sdp.
> Content-Disposition: session.
> Content-Length: 338.
> X-Designated-Service: fax/t38.
> .
> v=0.
> o=FreeSWITCH 1345708964 1345708968 IN IP4 3.3.3.3.
> s=FreeSWITCH.
> c=IN IP4 3.3.3.3.
> t=0 0.
> m=image 19892 udptl t38.
> a=T38FaxVersion:0.
> a=T38MaxBitRate:14400.
> a=T38FaxTranscodingMMR.
> a=T38FaxTranscodingJBIG.
> a=T38FaxRateManagement:transferredTCF.
> a=T38FaxMaxBuffer:72.
> a=T38FaxMaxDatagram:512.
> a=T38FaxUdpEC:t38UDPFEC.
>
>
> U 2012/08/23 15:34:34.043165 4.4.4.4:5060 -> 3.3.3.3:5060
> BYE sip:gw+provider-voip-tel at 3.3.3.3:5060;transport=udp;gw=provider-voip-tel SIP/2.0.
> Call-ID: 3bf65bb6-ed27-11e1-a810-1d8ba1d695aa.
> From: <sip:+888 at 4.4.4.4>;tag=SDkvc5299-1.45.133.551104+1+a1b50004+4166b8ad.
> To: "+777" <sip:+777 at provider.voip.tel>;tag=70aprjj2Z1QKK.
> CSeq: 693734810 BYE.
> Content-Length: 0.
> Reason: Q.850; cause=41;text="Temporary failure".
> .
>
>
>
> _________________________________________________________________________
> 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

-- 
Anthony Minessale II

FreeSWITCH http://www.freeswitch.org/
ClueCon http://www.cluecon.com/
Twitter: http://twitter.com/FreeSWITCH_wire

AIM: anthm
MSN:anthony_minessale at hotmail.com
GTALK/JABBER/PAYPAL:anthony.minessale at gmail.com
IRC: irc.freenode.net #freeswitch

FreeSWITCH Developer Conference
sip:888 at conference.freeswitch.org
googletalk:conf+888 at conference.freeswitch.org
pstn:+19193869900