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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=DE-AT link="#0563C1" vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'>Hello,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'>Today I stumble over this topic again by testing around with a peering partner which doesn’t support T.38 fax, so I checked the settings t38_decode and t38_force in the handbook but it doesn’t read like this is what I need.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'>So I take some time to think over about this topic…<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'>What should be solved: try to solve some internet connection problems between subscribers/peerings and the sipwise if fax could only be done with T.30 (G.711) cause subscriber or peering doesn’t support T.38. <br>so if think the solution could be that if one call-leg (subscriber to server or peering to server) support T.38, T.38 should be used on this call-leg independently if the other call-leg support it.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'>So the rtpengine should work as a man-in-the-middle fax transcoder/decoder for maximum fax stability to use T.38 on every call-leg where it could be possible.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'>In detail I try to explain it:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoNormal><b><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'>Outbound FAX (subscriber to peering):<o:p></o:p></span></b></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'>Case 1: If an invite is coming with T.30 from the subscriber, the sipwise should send an invite to the peering and ask if T.38 is supported or not. If supported the server should take the T.30 fax and transcode it to T.38. If not supported, pass-through.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'>Case 2: If an invite is coming with T.38 from the subscriber, the sipwise should send an invite to the peering and ask if T.38 is supported or not. If supported pass-through, if not supported, sipwise server should take the T.38 fax and transcode it to T.30 fax for the peering.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoNormal><b><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'>Inbound FAX (peering to subscriber):<o:p></o:p></span></b></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'>Case 1: If an invite is coming with T.30 from the peering, the sipwise should send an invite to the subscriber and ask if T.38 is supported or not. If supported the server should take the T.30 fax and transcode it to T.38. If not supported, pass-through.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'>Case 2: If an invite is coming with T.38 from the peering, the sipwise should send an invite to the subscriber and ask if T.38 is supported or not. If supported pass-through, if not supported, sipwise server should take the T.38 fax and transcode it to T.30 fax for the subscriber.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext;mso-fareast-language:DE-AT'>Is this working also in practice or is this a technical overkill and will bring more problems as it solves? In theory it sounds useful but who knows…<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext'>Any idea on this?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='color:windowtext'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=DE style='color:windowtext;mso-fareast-language:DE-AT'>Von:</span></b><span lang=DE style='color:windowtext;mso-fareast-language:DE-AT'> Spce-user <<a href="mailto:spce-user-bounces@lists.sipwise.com">spce-user-bounces@lists.sipwise.com</a>> <b>Im Auftrag von </b>Hohl Matthias<br><b>Gesendet:</b> Donnerstag, 15. November 2018 13:26<br><b>An:</b> 'Daniel Grotti' <<a href="mailto:dgrotti@sipwise.com">dgrotti@sipwise.com</a>>; <a href="mailto:spce-user@lists.sipwise.com">spce-user@lists.sipwise.com</a><br><b>Betreff:</b> Re: [Spce-user] T.38 to G.711a transcoding for peerings and vice versa<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Hello Daniel,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-US>I believe it would be a problem on subscriber side:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>From SPCE to Peering Server with G.711a for faxing would be less problem because the transport will be with Sync-Ethernet and with direct peering connection.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>But between subscriber PBX and SPCE there is often any kind of internet connection possible, and for this reason I think T.38 (leg from subscriber to SPCE) would make the things more stable like G.711a.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>So I think T.38 on subscriber side and G.711a on Peering side would be the most effective way to have successful fax services. Therefore SPCE has to transcode T.38 to G.711a for the peering or G.711a to T.38 for subscriber if the subscriber is supporting it.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>I hope I descriped it now better </span><span lang=EN-US style='font-family:"Segoe UI Emoji",sans-serif'>😊</span><span lang=EN-US><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=DE style='mso-fareast-language:DE-AT'>Von:</span></b><span lang=DE style='mso-fareast-language:DE-AT'> Spce-user <<a href="mailto:spce-user-bounces@lists.sipwise.com">spce-user-bounces@lists.sipwise.com</a>> <b>Im Auftrag von </b>Daniel Grotti<br><b>Gesendet:</b> Donnerstag, 15. November 2018 12:00<br><b>An:</b> <a href="mailto:spce-user@lists.sipwise.com">spce-user@lists.sipwise.com</a><br><b>Betreff:</b> Re: [Spce-user] T.38 to G.711a transcoding for peerings and vice versa<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal style='margin-bottom:12.0pt'><tt><span style='font-size:10.0pt'>Hi,</span></tt><span style='font-size:10.0pt;font-family:"Courier New"'><br><tt>frankly I don't see the problem.</tt><br><tt>I would just enable t.38 anyway, in case the t38 re-negotiation fails (e.g with your peering server) the fax should go in G711, as falback.</tt><br><br><br></span><span style='mso-fareast-language:DE-AT'><o:p></o:p></span></p><pre>-- <o:p></o:p></pre><pre>Daniel Grotti<o:p></o:p></pre><pre>Head of Customer Support<o:p></o:p></pre><pre>Sipwise GmbH, Campus 21/Europaring F15<o:p></o:p></pre><pre>AT-2345 Brunn am Gebirge<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Office: +43(0)130120332<o:p></o:p></pre><pre>Email: <a href="mailto:dgrotti@sipwise.com">dgrotti@sipwise.com</a><o:p></o:p></pre><pre>Website: <a href="https://www.sipwise.com">https://www.sipwise.com</a><o:p></o:p></pre><div><p class=MsoNormal>On 11/15/18 11:45 AM, Hohl Matthias wrote:<o:p></o:p></p></div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><p class=MsoNormal>Hello,<o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal><span lang=EN-US>Today I got the information that A1 Telekom is not supporting T.38 in there IC network.</span><o:p></o:p></p><p class=MsoNormal><span lang=EN-US>Only if the traffic is a Transit Call, T.38 will be supported as “Pass-Through”.</span><o:p></o:p></p><p class=MsoNormal><span lang=EN-US>All other Fax Calls with a Reinvite to T.38 will be “not acceptable here”.</span><o:p></o:p></p><p class=MsoNormal><span lang=EN-US> </span><o:p></o:p></p><p class=MsoNormal><span lang=EN-US>For better fax stability I want to allow T.38 for my subscribers.</span><o:p></o:p></p><p class=MsoNormal><span lang=EN-US>Therefore I want to allow T.38 just on subscriber side. On peering side, T.38 has to be transcoded to G.711a, if the destination network is A1 Telekom. Also if a FAX comes from A1 with G.711a it should be transcoded to T.38 for our subscribers, of the subscriber support T.38.</span><o:p></o:p></p><p class=MsoNormal><span lang=EN-US>IS it possible to implement this transcoding option in any way on the SPCE mr6.5.1? Maybe with a SEMS patch?</span><o:p></o:p></p><p class=MsoNormal><span lang=EN-US> </span><o:p></o:p></p><p class=MsoNormal><span lang=EN-US>Would be nice if someone has an idea to solve this </span><span lang=EN-US style='font-family:"Segoe UI Emoji",sans-serif'>😊</span><o:p></o:p></p><p class=MsoNormal><span lang=EN-US> </span><o:p></o:p></p><p class=MsoNormal><span style='mso-fareast-language:DE-AT'>Mit freundlichen Grüßen,</span><o:p></o:p></p><p class=MsoNormal><span style='mso-fareast-language:DE-AT'>Matthias Hohl</span><o:p></o:p></p><p class=MsoNormal><span style='mso-fareast-language:DE-AT'> </span><o:p></o:p></p><p class=MsoNormal> <o:p></o:p></p><p class=MsoNormal style='margin-bottom:12.0pt'><span style='mso-fareast-language:DE-AT'><o:p> </o:p></span></p><pre>_______________________________________________<o:p></o:p></pre><pre>Spce-user mailing list<o:p></o:p></pre><pre><a href="mailto:Spce-user@lists.sipwise.com">Spce-user@lists.sipwise.com</a><o:p></o:p></pre><pre><a href="https://lists.sipwise.com/listinfo/spce-user">https://lists.sipwise.com/listinfo/spce-user</a><o:p></o:p></pre></blockquote><p class=MsoNormal><span style='mso-fareast-language:DE-AT'><o:p> </o:p></span></p></div></body></html>