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PHY Errors, Noise Floor, Airtime interpretation in ZD

I would like to find out what values for PHY Errors, Noice Floor, Airtime total, busy, RX, TX are good and what values are bad?

If I'm correctly informed, this is what I know:
PHI Errors of < 20000 is acceptable,
Noise Floor above -85 is bad, below -110 is excellent.
Total Airtime 100% would be great since that means the capacity is fully used, total airtime of < 20 could mean there is a lot of interference, or hardly any users.

Is this correct?
What can I learn from the other Airtime values (busy, rx, tx)? Are the values different for 2.4 and 5 GHz? (i.e 2.4GHz NF should be below -90, 5GHz NF should be below -85?)

I'm basically looking for an answer on this question: what values of which fields of the monitoring page in the ZD indicate that an AP is doing great or needs attention?

Valued Contributor
You've asked a great question and I hope for a nice discussion on this.

It's a bit subjective and it's not quite clear cut what is acceptable and what not. Maybe just one of many clients will cause most of the errors and others will do less and work fine.

But in any case I would not consider PHY errors of s a good compromise between price/performance.

New Contributor II
Hi Jelle ,

Here are our numbers as seen on a 7762AC deployed indoors, during a tech conference. At the moment we recorded these numbers, it was almost impossible to get a reliable connection on the 2.4 GHz frequency.

Radio: 802.11g/n
# of Aurhorized Client Devices: 69
Noise Floor: -88
PHY Errors: 831
% AirTime (total/busy/RX/TX): 87/47/33/8

%Retries/%Drops: 7.14 / 0.00
TX Power: Min
Background scanning: enabled

Valued Contributor
Well you've got low retry rate which is good, also your Air Time is at 87% but the Air Time declared as busy is at 47% and the noise floor is at -88dBm.

I guess there are quite a few other (or your) networks around your AP that keep triggering this APs and the STAs connected to it CCA.

This could also be from people bringing their MiFis. How many networks do are there?

You could try using a higher directional antenna or 7762-AC-S and stop transmitting 802.11b rates. Those travel far and cause a lot of issues. You do that over CLI.

So if I zoom in on Airtime:
High "total" is good, if "busy" is not a big part of it?
Or even: if busy < rx + tx, the AP is doing ok?