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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>No debate here. The model I like is that there is something built-in to the browser (say, TFRC or some variant), but the hooks are available to allow an application to customize it.<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><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>-Jonathan R.<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><span lang=ET style='font-size:11.0pt;font-family:"Courier New";color:#1F497D'>Jonathan D. Rosenberg, Ph.D. SkypeID: jdrosen<o:p></o:p></span></p><p class=MsoNormal><span lang=ET style='font-size:11.0pt;font-family:"Courier New";color:#1F497D'>Chief Technology Strategist Mobile: +1 (732) 766-2496<o:p></o:p></span></p><p class=MsoNormal><span lang=ET style='font-size:11.0pt;font-family:"Courier New";color:#1F497D'>Skype SkypeIn: +1 (408) 465-0361<o:p></o:p></span></p><p class=MsoNormal><span lang=ET style='font-size:11.0pt;font-family:"Courier New";color:#1F497D'>jdrosen@skype.net http://www.skype.com<o:p></o:p></span></p><p class=MsoNormal><span lang=ET style='font-size:11.0pt;font-family:"Courier New";color:#1F497D'>jdrosen@jdrosen.net http://www.jdrosen.net<o:p></o:p></span></p></div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";color:windowtext'> Matthew Kaufman [mailto:matthew.kaufman@skype.net] <br><b>Sent:</b> Tuesday, January 25, 2011 7:47 AM<br><b>To:</b> Rosenberg, Jonathan<br><b>Cc:</b> 'Saverio Mascolo'; 'Stefan Håkansson LK'; 'Cullen Jennings'; tom_harper@logitech.com; 'Justin Uberti'; 'Harald Alvestrand'; rtc-web@alvestrand.no; 'Peter Musgrave'<br><b>Subject:</b> Re: [RTW] Rate control and codec adaption (Re: [dispatch] The charter formerly know as RTC-WEB take 3)<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Agreed, but for the purpose of this discussion I believe that rate control of some sort should also be a MUST.<br><br>Web browsers are extremely prevalent, and we hope that RTC use in browsers will be high, and so it would be good for the Internet for browsers to have sending rate control. Note that this is at the protocol level... so send rate must be controlled whether the codec can have its rate adjusted downward so as to not require the protocol level to enforce or not.<br><br>For interoperability, it is also required that the feedback mechanism from one end to the other be standardized, even if the way that feedback is used to control send rate and/or codec selection or codec rate selection is proprietary and/or extensions to the feedback are also sent for endpoints that understand the (possibly proprietary) extension(s).<br><br>Matthew Kaufman<br><br>On 1/25/2011 7:38 AM, Rosenberg, Jonathan wrote: <o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>It’s a proprietary algorithm of our own design, supported by some protocols which exchange feedback in real-time between endpoints. We’re constantly tweaking it based on user feedback and technical statistics we collect.</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>Indeed – as many folks are aware, rate adaptation has always been an area of innovation and differentiation. RTP has provided the tools for feedback but has allowed implementations to do whatever they want. I think it is important that this continues to be the case in the web world – that folks designing RTC applications can innovate and define their own versions of these algorithms.</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> </span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>Thanks,</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'>Jonathan R.</span><o:p></o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif"'> </span><o:p></o:p></p><p class=MsoNormal><span lang=ET style='font-size:11.0pt;font-family:"Courier New";color:#1F497D'>Jonathan D. Rosenberg, Ph.D. SkypeID: jdrosen</span><o:p></o:p></p><p class=MsoNormal><span lang=ET style='font-size:11.0pt;font-family:"Courier New";color:#1F497D'>Chief Technology Strategist Mobile: +1 (732) 766-2496</span><o:p></o:p></p><p class=MsoNormal><span lang=ET style='font-size:11.0pt;font-family:"Courier New";color:#1F497D'>Skype SkypeIn: +1 (408) 465-0361</span><o:p></o:p></p><p class=MsoNormal><span lang=ET style='font-size:11.0pt;font-family:"Courier New";color:#1F497D'><a href="mailto:jdrosen@skype.net">jdrosen@skype.net</a> <a href="http://www.skype.com">http://www.skype.com</a></span><o:p></o:p></p><p class=MsoNormal><span lang=ET style='font-size:11.0pt;font-family:"Courier New";color:#1F497D'><a href="mailto:jdrosen@jdrosen.net">jdrosen@jdrosen.net</a> <a href="http://www.jdrosen.net">http://www.jdrosen.net</a></span><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>