how to find if a station is slowing down the AP

RouterOS Wireless Networking
1

Hello,

I have a base station with RB411AH + R52Hn using a 17dBi 90° dual pol sector.

Is there a way to identify if some stations are slowing down the AP causing a degradation in performance?

My WLAN config is:

/interface wireless
set 0 band=5ghz-onlyn basic-rates-a/g="" basic-rates-b="" \
    default-forwarding=no disabled=no frequency=5580 \
    ht-basic-mcs=mcs-0,mcs-2,mcs-3,mcs-4,mcs-9,mcs-10,mcs-11 ht-rxchains=0,1 \
    ht-supported-mcs=mcs-0,mcs-2,mcs-3,mcs-4,mcs-9,mcs-10,mcs-11 ht-txchains=\
    0,1 hw-retries=10 l2mtu=2290 max-station-count=70 mode=ap-bridge mtu=1800 \
    nv2-cell-radius=10 nv2-preshared-key=XXXXX nv2-qos=frame-priority \
    nv2-queue-count=4 nv2-security=enabled periodic-calibration=enabled \
    preamble-mode=short radio-name=RADIOA rate-set=configured scan-list=\
    5470-5725 security-profile=WPA2-PSK-2 supported-rates-a/g="" \
    supported-rates-b="" tdma-period-size=3 tx-power=20 tx-power-mode=\
    all-rates-fixed wds-mode=dynamic wireless-protocol=nv2

Registration table:
regtable.png

2

My method:
Find the best station according to the one with best signal-strength
In registration-table select all records and press “reset”
Now order by “Tx/Rx Bytes” descending

From AP start a TCP BWTest in send mode (TCP Connection count=4) to the best station
Wait a moment (your client go in the first position of reg-table)
Now start to put the second, third, ecc.. in accesst list with autentication=no

When you see a better badwidth then “that” station was a problem (second, third, ecc..)

3

The TX/RX CCQ is the value you are looking for, just sort and see the worst CCQ - that client is most probably slowing down your AP.

4

Not always ccq show bad stations.
I’ve some stations with 50% of ccq and good modulation bad very bad throughput.

I also remember that CCQ is completely unreliable when doesn’t pass traffic over the wireless interface.

5

I agree with you but at least the CCQ shows that station is not ok if the value is low. 50% is quite bad for reasonable modulation I would say.

As far as I can see the low CCQ without any traffic is just at the time the client connects to the AP, when it start to pass traffic and then traffic goes to 0 again, the CCQ and modulation stay the same like with traffic.