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<p class="MsoNormal"><span style="color:#1F497D">If you can get something like TBCT working, you can release the media back upstream somewhere along the line.<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">Other than that, I suppose that you could jack the TTL with iptables. Tough call, because the audio delay after that many IP hops will probably trash the call.<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>
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<p class="MsoNormal"><span style="color:#1F497D">David<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> VoiceOps [mailto:voiceops-bounces@voiceops.org]
<b>On Behalf Of </b>Ujjval Karihaloo<br>
<b>Sent:</b> Thursday, May 09, 2013 21:30<br>
<b>To:</b> voiceops@voiceops.org<br>
<b>Subject:</b> [VoiceOps] Hairpin Call from certain PBXs - No Audio issue<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Hi Team:<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal"> Have you all seen issues with hairpin calls from PSTN<span style="font-family:Wingdings">à</span> ITSP (Broadsoft/ACME)<span style="font-family:Wingdings">à</span> SIP Trunk – which in turn forwards the call back out the SIP trunk
to the PSTN and there is no Audio in either direction (Transfer via Auto-attendant OR Blind – Attended Xfer works as Media is anchored/reinitiated on PBX)<o:p></o:p></p>
<p class="MsoNormal">Having worked on a few PBXs (Allworx, Zultys) that cause this issue on ACME/Broadsoft Sip trunk setup – we see RTP in both direction on our traces, but due to the pass through RTP nature of this call flow, the TTL get way down to 5-6 in
some cases, and that is what I believe is the issue, and our upstream vendors like Level3, Bandwidth etc suggest the same.<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">Other than implementing a RTP repeater of sorts, I don’t see an alternative. Ideas appreciated<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">Thx<o:p></o:p></p>
<p class="MsoNormal">Ujjval<o:p></o:p></p>
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