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<div class="moz-cite-prefix">Am 19.04.2013 00:22, schrieb
<a class="moz-txt-link-abbreviated" href="mailto:dpreed@reed.com">dpreed@reed.com</a>:<br>
</div>
<blockquote cite="mid:1366323746.07313097@apps.rackspace.com"
type="cite">
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<p>7 WiFi LANs tend to interact in interesting ways. I do believe
you can probably model the physics if you have the complete
physical model of the environment, including the motion of
people, objects, etc. and also a model of the specific antenna
locations and positions, as well as precise timings and indices
of refraction.</p>
</blockquote>
<br>
O.k., that's difficult.<br>
<br>
<blockquote cite="mid:1366323746.07313097@apps.rackspace.com"
type="cite">
<p>Â </p>
<p>But this is not the real problem. The real problem is that the
programs and humans that generate the traffic generate that
traffic dependent on the communications performance they
observe. </p>
</blockquote>
<br>
Don't blame my neighbours ;-) <br>
<br>
However, I agree. That's the real problem. I cannot simulate my
neighbours, neither their behaviour.<br>
<br>
<blockquote cite="mid:1366323746.07313097@apps.rackspace.com"
type="cite">
<p>That is, I don't usually click on a link until I've received
the page and had it displayed, but not always - sometimes I
interrupt the process and go on to the next link. Similarly,
the low level MAC protocol involves several components of
behavior. If, for example, noise is detected at a certain level
(way below the signalling levels) in the 4 microseconds before a
transceiver is about to send a packet, the packet will not be
sent. But during this interval other stations will hear
*different* noise, because noise is not equi-potential
simultaneously across the stations on the 7 WLANs.  So small
variation during intervals as short as 4 microseconds can have
amplified effects.</p>
</blockquote>
<br>
In this context, I remember a recent discussion in the German part
of the usenet: There are apparently different strategies how WLAN AP
choose their channel, particularly when adapting to a certain
channel load situation. From that, I conclude, we would have to
simulate not only different brands and different software releases.<br>
<br>
<pre class="moz-signature" cols="72">--
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