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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">>Support for RTP header extensions is probably going to be needed in the future for other applications (e.g., transmitting some WebRTC streams), but I want to >understand where/why people might already be using them for other purposes.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">An application for the RTP header extensions is in VoIP Air Traffic Management for radio communication. The EUROCAE standards ED137 part 1: Radio states:<o:p></o:p></p>
<p class="MsoNormal">“The Real time Transport Protocol Header Extension will be employed to transport the following signalling information in real time:<o:p></o:p></p>
<p class="MsoNormal" style="text-indent:36.0pt">a) PTT (Push To Talk)<o:p></o:p></p>
<p class="MsoNormal" style="text-indent:36.0pt">b) Aircraft Call (A/C call), also nominated Squelch (SQL);<o:p></o:p></p>
<p class="MsoNormal" style="text-indent:36.0pt">c) Quality index (used for the Best Signal Signalling feature)<o:p></o:p></p>
<p class="MsoNormal" style="text-indent:36.0pt">d) Time stamping information (used for CLIMAX application)<o:p></o:p></p>
<p class="MsoNormal" style="text-indent:36.0pt">e) Reserved field for proprietary applications f) Keep alive message<o:p></o:p></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">“<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Ref:
<a href="http://startrinity.com/voip/Resources/ED-137_Interoperability_Standards_for_VoIP_ATM_Components_Part_1_Radio.pdf">
http://startrinity.com/voip/Resources/ED-137_Interoperability_Standards_for_VoIP_ATM_Components_Part_1_Radio.pdf</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal">ED137 part 4: Recording, describes how to record ATM voice communications and metadata using RTSP.<span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<div>
<p class="MsoNormal" style="text-autospace:none"><b><span style="font-size:9.0pt;font-family:"Arial","sans-serif";color:#333333;mso-fareast-language:SV">Jan Rørgård Hansen<o:p></o:p></span></b></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="DA" style="font-size:8.0pt;font-family:"Arial","sans-serif";color:#333333;mso-fareast-language:SV">Senior Engineer<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="DA" style="font-size:8.0pt;font-family:"Arial","sans-serif";color:#333333;mso-fareast-language:SV">Saab Danmark<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:8.0pt;font-family:"Arial","sans-serif";color:#333333;mso-fareast-language:SV">Security & Defence Solutions<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:8.0pt;font-family:"Arial","sans-serif";color:#333333;mso-fareast-language:SV"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="EN-US" style="font-size:8.0pt;font-family:"Arial","sans-serif";color:#333333;mso-fareast-language:SV">Direct +45 36383000<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="FR" style="font-size:8.0pt;font-family:"Arial","sans-serif";color:#333333;mso-fareast-language:SV">jan.r.hansen@dk.saabgroup.com<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="FR" style="font-size:8.0pt;font-family:"Arial","sans-serif";color:#333333;mso-fareast-language:SV"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><b><span lang="DA" style="font-size:9.0pt;font-family:"Arial","sans-serif";color:#333333;mso-fareast-language:SV">Saab
<o:p></o:p></span></b></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="DA" style="font-size:8.0pt;font-family:"Arial","sans-serif";color:#333333;mso-fareast-language:SV">Alsion 2<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="DA" style="font-size:8.0pt;font-family:"Arial","sans-serif";color:#333333;mso-fareast-language:SV">DK – 6400 Sønderborg
<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span lang="DA" style="font-size:8.0pt;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:SV"><a href="http://www.saabgroup.com/">www.saabgroup.com</a><o:p></o:p></span></p>
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<p class="MsoNormal" style="text-autospace:none"><span style="font-size:9.0pt;font-family:"Arial","sans-serif";color:#1F497D"><img border="0" width="133" height="42" id="Picture_x0020_1" src="cid:image002.jpg@01D08D6F.F9105DB0" alt="Saab AB"></span><span lang="DA" style="font-size:9.0pt;font-family:"Arial","sans-serif";color:#1F497D"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:50%;text-autospace:none"><span lang="DA" style="font-size:8.0pt;line-height:50%;font-family:"Arial","sans-serif";color:#1F497D;mso-fareast-language:SV"><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:8.0pt;font-family:"Arial","sans-serif";color:#333333;mso-fareast-language:SV">------------------------<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><i><span style="font-size:8.0pt;font-family:"Arial","sans-serif";color:#333333;mso-fareast-language:SV">This e-mail is private and confidential between the sender and the addressee.
<o:p></o:p></span></i></p>
<p class="MsoNormal" style="text-autospace:none"><i><span style="font-size:8.0pt;font-family:"Arial","sans-serif";color:#333333;mso-fareast-language:SV">In the event of misdirection, the recipient is prohibited from using, copying or
<o:p></o:p></span></i></p>
<p class="MsoNormal"><i><span style="font-size:8.0pt;font-family:"Arial","sans-serif";color:#333333;mso-fareast-language:SV">disseminating it or any information in it. Please notify the above if any misdirection.</span></i><span lang="EN-US" style="font-size:8.0pt;font-family:"Arial","sans-serif";color:#1F497D"><o:p></o:p></span></p>
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