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<div class="moz-cite-prefix">On 24/07/2013 1:21 AM, James Braunegg
wrote:<br>
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<p class="MsoPlainText">Dear Andrew<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">I would recommend using iperf server /
client setup.<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">Testing international bandwidth is
tricky when using TCP traffic as it doesn’t really paint a
correct picture…..due to TCP Windowing, what you want to do
is a UDP test.</p>
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No, what you want to do is a multi-thread TCP test, not a UDP test.
5 or 6 parallel TCP threads, with each thread occupying ~ 30% window
depth at steady-state, will make sure that results aren't corrupted
by windowing issues on a single thread, or the back-off/slow-start
sawtooth behaviour when a packet is lost.<br>
<br>
Of course that only gives you a result for a short period of time,
but it will certainly identify the bottleneck aggregate rate. For
trying to measure throughput in the multi-hundreds-Mbps range, no
single-packet-stream method either TCP or UDP is going to give a
useful result.<br>
<br>
P.<br>
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