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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>I’m having problems faxing if the B leg offers T.38. Several scenarios, but always the same result.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>First, the architecture<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>FAX <span style='font-family:Wingdings'>à</span> ATA (T.38 optional) <span style='font-family:Wingdings'>à</span> FS <span style='font-family:Wingdings'>à</span> Carrier <span style='font-family:Wingdings'>à</span> Destination (Possibly another carrier (PSTN) and the fax machine)<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>On my ATA, T.38 is enabled (Auto Detect).<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>If the destination supports T.38, the Carrier will offer it to Freeswitch. If the Destination doesn’t support T.38, the B leg doesn’t offer it and the faxes go through.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’ve set Freeswitch as: <o:p></o:p></p><p class=MsoNormal> <action application="set" data="fax_enable_t38=true"/><o:p></o:p></p><p class=MsoNormal> <action application="export" data="t38_passthru=true"/> <o:p></o:p></p><p class=MsoNormal>When that’s the case, and the B leg offers T.38, Freeswitch passes through the offer and the ATA responds, 3 times. But the response never gets sent to the B leg, so it terminates the call after about 30 seconds.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>When I set Freeswitch as: <o:p></o:p></p><p class=MsoNormal> <action application="set" data="fax_enable_t38=false"/><o:p></o:p></p><p class=MsoNormal>The B leg still offers T.38 if its other side is capable. Freeswitch doesn’t pass the offer through and the B leg terminates the call after about 30 seconds.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’m running on a recent git ( FreeSWITCH Version 1.0.head (git-86d757d 2011-05-17 22-51-47 -0500) ).<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’ve had no success attempting to configure FS as a gateway. Frankly, T.38 “passthrough” has had the most success, mostly when the other ends aren’t T.38 capable and it stays in G711u.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Is there something else I need to do to enable T.38 in passthrough mode? <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thank you,<br>Rob Morin<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>PS – I can provide tcpdumps of this, or whatever else is necessary.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>