Sanity Check: How to Scan

radicalbiscuit said: Should I be disconnected from the network when I initiate a scan? I just want to make sure being connected at the time of scanning doesn’t add noise or interference into the record.

It really doesn’t matter. You can be connected or disconnected from the network in question and still handling a very successful and true-to-life survey.

radicalbiscuit said: Oh, and I’m quite familiar with signal to noise ratio. So I’m a little unsure as to what the difference between SNR and signal to interference ratio is. In the scans I’ve run so far, signal to interference has been much lower (worse) than SNR. What can I extrapolate from each?

The signal-to-interference ratio is similar to the signal-to-noise ratio, but in this case the interference is specific to co-channel interference from other radio transmitters. According to some opinions wireless devices will work reliably with the SIR ratio of 0dB (decibels) or less. If you click on the measurement markers on the map, you can see the exact ratio(s) for each location.

The signal-to-noise ratio compares the level of the Wi-FI signal to the level of background noise. A ratio of 10-15dB is the accepted minimum to establish an unreliable connection; 15-25dB (decibels) is usually considered bad; 25-40dB is a good signal and a ratio of 41dB or higher is considered excellent. If you click on the measurement markers on the map, you can see the exact ratio(s) for each location.

Hope this helps.