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<p class=MsoNormal>Hi,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Winpcap 4.0.2 is being used on a Windows Server 2008 box to
capture UDP-tunnelled streaming media (IP multicast) packets and then present de-capsulated/original
multicasts for playback in windows media player on box. Depending on the
stream, the bitrate may be 500-600kbps. <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>The underlying multicast packets are being IP fragmented at
source, so each fragment is UDP-tunnelled so arrives as its own UDP packet,
becoming an IP fragment after tunnel decapsulation. <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I’m not the developer here but I’m presuming
once the tunnelled packets are decapsulated they are written back to NPF for
subsequent presentation to the IP layer and normal IP processing.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>The on-box media player is showing up to 40% packet loss and
wonder if this could be due to the NPF not being capable somehow of processing
packets under these higher bitrate conditions? The path between source and
receiver is just a single-hop LAN and I’m confident the packet loss is not
happening in the network.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Or perhaps certain parameters need setting accordingly?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>The network adapter is a Broadcom NetXtreme Gigabit Ethernet
adapter.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Any suggestions would be greatly appreciated.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thanks<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Tony<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
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