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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-family:"Courier New";color:black'>Thanks for the confirmation Ross.<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New";color:black'>We do use UDP, i.e. the default, which makes this lag so very strange. I can clearly see all frames being received on the first UDP-port (when viewing ports in use with e.g. TCPView).<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New";color:black'>This 2s lag has been observed three times in total over the last four months, on different workstations. However, each test-workstation cycles through a lot of streams, each typically making around 100,000 connections a day, so it's a very rare occurrence. The fact that it continues to happen once it started, i.e. for every subsequent connection using the same event loop/video pane is even more confusing.<o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New";color:black'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-family:"Courier New";color:black'>/Claes</span><span style='font-family:"Calibri","sans-serif";color:black'><o:p></o:p></span></p><p class=MsoNormal><span style='font-family:"Calibri","sans-serif";color:black'><o:p> </o:p></span></p><div><p class=MsoNormal style='margin-left:.5in'>Of course our code doesn't buffer anything for 2 seconds. (The 'packet reordering' queue delays incoming packets for at most the 'packet reordering threshold' - which is, by default, only 100 ms - and only if packet loss occurs.)<o:p></o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p></div><div><p class=MsoNormal style='margin-left:.5in'>The delay is obviously caused by the TCP implementation - i.e., in the OSs of your server and client. This is not a bug; this is simply TCP's way of ensuring reliable data delivery, in the face of high data rates and lossy networks. To overcome this, either send less, or stream via UDP instead of TCP. (You should stream RTP-over-TCP *only* if there's a firewall - between the server and client - that blocks UDP packets.)<o:p></o:p></p></div><p class=MsoNormal style='mso-margin-top-alt:0in;margin-right:0in;margin-bottom:12.0pt;margin-left:.5in'><o:p> </o:p></p><div><p class=MsoNormal style='margin-left:.5in'><span class=apple-style-span><span style='font-size:13.5pt;font-family:"Helvetica","sans-serif";color:black'>Ross Finlayson</span></span><span style='font-size:13.5pt;font-family:"Helvetica","sans-serif";color:black'><br><span class=apple-style-span>Live Networks, Inc.</span><br><span class=apple-style-span><a href="http://www.live555.com/">http://www.live555.com/</a></span></span> <o:p></o:p></p></div><p class=MsoNormal style='margin-left:.5in'><o:p> </o:p></p></div></body></html>