I saw this post on a forum while investigating other issues and had to note it down for you and for my own reference! Finally a definitive answer easily understood to a question I have had for ages regarding determining wireless performance
SNR (Signal-to-Noise Ratio) is a ratio based value that evaluates
your signal based on the noise being seen. So let's look at the
components of the SNR and they see how to determine it. SNR is
comprised of 2 values and is measured as a positive value between 0db
and 120db and the closer it is to 120db the better: Signal Value and
Noise Value typically these are expressed in decibels (db).
So we will look at the Signal (Also known as RSSI) first this value is
measured in decibels from 0 (zero) to -120 (minus 120) now when looking
at this value the closer to 0 (zero) the stronger the signal is which
means it's better, typically voice networks require a -65db or better
signal level while a data network needs -80db or better. Normal range
in a network would be -45db to -87db depending on power levels and
design; since the Signal is affected by the APs transmit power &
antenna aswell as the clients antenna.
Great stuff, found the post here:
Also worth pointing out as per his post that the 7925g handsets can actually be used to perform site surveys! Another handy trick!
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