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I would like to measure how different applications will perform under poor Signal Quality.

Where Signal Quality is measured by:

Signal / Noise * SNR = Signal Quality  
  -80  /  -90  * 10  = 8.9%

What are the best tools/hardware available (not too expensive) to make such measurements possible and easy? I am looking for something a little better than turning on a microwave or stacking a few bricks around my access point.


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up vote 3 down vote accepted

This depends entirely on your access point hardware.

For example, on Tomato firmware go to Advanced -> Wireless -> Transmit Power and set a new value to lower the signal strength.

Another (possibly better approach) would be to add rules into your local firewall to manipulate the traffic parameters.

For example if you're on Linux, iptables -t mangle -A INPUT -m statistic --mode random --probability 0.01 -j DROP introduces an average of a 1% packet loss.

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Give it a tinfoil hat? :)

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That only keeps aliens and governments out. :-) – Scott Lundberg Jan 22 '10 at 21:03
I'm pretty sure it would hurt the signal as well. Not very configurably, but hey! – Bill Weiss Jan 22 '10 at 23:12
Fully customizable with scissors and some paper clips. :) – yhw42 Feb 4 '11 at 20:17
+1: Multiple layers of aluminum foil will attenuate a Wi-Fi signal very effectively. Foil is thin enough that the level of attenuation can be adjusted by varying the number of layers. Additionally, this solution is vendor-neutral. – Skyhawk Nov 6 '11 at 19:35

If you want your testing to be controlled and reproducible, you probably want to use a network simulator/emulator and take real-life wireless (which is at the mercy of every cordless phone, microwave and other wifi user for 100s of metres around) out of the picture. There is at least one (free one) specifically designed for wireless: OpenWNS.

If that's overkill... well what's actually wrong with using the bricks ?

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Someone has written a Faulty Network Router for simulating things like this.

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