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</o:shapelayout></xml><![endif]--></head><body lang=EN-CA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D'>Hi;<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>I am attempting to get T38 Fax working between two FS/FusionPBX installations using mod_spandsp. I am unable to get into T.38 mode, T.30 used, successful fax.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Note that zrtp is disabled for fax calls, due to T38 udpl (not rtp media) incompatibility<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Thanks Brian West!: “T.38 Fax takes place over UDPTL, There for it can NOT be encrypted as there was never really a standard for doing so.”<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Details (both FS’s):<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>SIP Provider: freephoneline.ca (claims T38 capable)<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>freeswitch - 1.4.18<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>x86_64<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Topology:<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>FS#1: rossco.org, using FusionPBX web GUI to send fax<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>FS#2:rossco.duckdns.org, using spandsp extension to receive fax<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>(spandsp txfax, x1020)FS#1 -> cloud -> FS#2(spandsp rxfax, x9000)<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Key variables for fax sender (FS#1), during call:<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>$domain= rossco.org<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Spandsp Fax extension: 1020<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>t38_passthru = false<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>zrtp_secure_media = false<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>fax_enable_t38 = true<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>fax_enable_t38_request = true<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>fax_use_ecm = off<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>inbound-late-negotiation = true<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>ignore_early_media = false<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Key variables for fax receiver (FS#2), during call:<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>$domain= rossco.duckdns.org<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Spandsp Fax extension: 9000<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>t38_passthru = false<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>zrtp_secure_media = false<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>fax_enable_t38 = true<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>fax_enable_t38_request = true<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>fax_use_ecm = off<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>inbound-late-negotiation = true<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>ignore_early_media = false<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Full Logs w/siptrace:<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Sender(rossco.org): <a href="https://pastebin.freeswitch.org/24115">https://pastebin.freeswitch.org/24115</a><o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Receiver(rossco.duckdns.org): <a href="https://pastebin.freeswitch.org/24116">https://pastebin.freeswitch.org/24116</a><o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Note that the SDP’s are correct for T38:<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>590fc4c4-3035-438e-a4c7-4a9d8e51ee42 v=0<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>590fc4c4-3035-438e-a4c7-4a9d8e51ee42 o=FreeSWITCH 1428750600 1428750602 IN IP4 198.48.238.130<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>590fc4c4-3035-438e-a4c7-4a9d8e51ee42 s=FreeSWITCH<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>590fc4c4-3035-438e-a4c7-4a9d8e51ee42 c=IN IP4 198.48.238.130<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>590fc4c4-3035-438e-a4c7-4a9d8e51ee42 t=0 0<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>590fc4c4-3035-438e-a4c7-4a9d8e51ee42 m=image 16448 udptl t38<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>590fc4c4-3035-438e-a4c7-4a9d8e51ee42 a=T38FaxVersion:0<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>590fc4c4-3035-438e-a4c7-4a9d8e51ee42 a=T38MaxBitRate:14400<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>590fc4c4-3035-438e-a4c7-4a9d8e51ee42 a=T38FaxFillBitRemoval<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>590fc4c4-3035-438e-a4c7-4a9d8e51ee42 a=T38FaxRateManagement:transferredTCF<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>590fc4c4-3035-438e-a4c7-4a9d8e51ee42 a=T38FaxMaxBuffer:2000<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>590fc4c4-3035-438e-a4c7-4a9d8e51ee42 a=T38FaxMaxDatagram:400<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>590fc4c4-3035-438e-a4c7-4a9d8e51ee42 a=T38FaxUdpEC:t38UDPRedundancy<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Questions:<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>1 - According to my interpretation of logs, T38 is not negotiated, despite T38 SDP’s<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>2 - What am I missing?<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Thanks;<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Bill Ross<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span lang=EN-US style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:#1F497D;mso-fareast-language:EN-CA'><o:p> </o:p></span></b></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p></div></body></html>