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I notice a problem when viewing 802.11 (wifi) client status on a Cisco 1242AG AP. enter image description here

My question is about the "Signal to Noise (dBm)" field.

I think that field should be called "Signal to Noise rate"(SNR) . It is a rate , so it should not be called a (dBm) value.

The upper right help link does not tell me well, which links to

enter image description here

You see, not even referring to word of "Signal to Noise (dBm)" but instead "Signal Quality".

Signal Quality - The percentage of signal quality that is good. If this percentage is low, the station may be on the fringe of the coverage area and should be moved closer to the access point.

Then, what is the meaning of the value(23 in my image)? It is a percent value, or the rate of signal power and noise power?

Cisco IOS version:

Product/Model Number: AIR-AP1242AG-C-K9
Top Assembly Serial Number: FCW1336U0CH
System Software Filename: c1240-k9w7-tar.124-10b.JDA3
System Software Version: 12.4(10b)JDA3
Bootloader Version: 12.4(13d)JA

enter image description here

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up vote 3 down vote accepted

The SNR is actually the difference between the signal level (in dBm) and the noise level (in dBm). An SNR of 20 is the goal for a stable WiFi link. From a signal level of -72 and an SNR of 23, you can conclude that the noise level is -95dBm, which is a typical WiFi noise floor for 2.4GHz.

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