topic Re: Calculate drop rate for individual user on ZD ? in Wireless Questions and Best Practices

Calculate drop rate for individual user on ZD ?

karl_lavender_7 — Sat, 12 Mar 2016 20:41:55 GMT

Just wondering if I am looking at an individual user stats on the ZD, I get the TX packets count and the TX retries count.

Am I right in just doing TxRetries/TxTotalPackets to get an approximate drop percentage for that user ? Or does the Tx total packets also include all the retries in that statistic ?

Re: Calculate drop rate for individual user on ZD ?

michael_brado — Mon, 14 Mar 2016 23:11:57 GMT

Look at the AP Support Info file, saved while you have a bunch of clients. Under the WLAN correspoding
to your SSIDs, you can see connected client statistics by MAC address, like this:

STA: 28:92:4a:bb:d1:4c
    rx_data_frm 107 rx_mgt_frm 4 rx_bytes 59649 rx_dup 1
    tx_data_frm 23 tx_mgmt_frm 6 tx_bytes 2198
    tx_assoc 2 tx_auth 1
    good_tx_frms 29 good_rx_frms 111 tx_retries 1
    tx_rate 48000 rx_crc_errs 31
    ack_rssi 32 rx_rssi 41

STA: e0:75:7d:61:6a:59
    rx_data_frm 134 rx_mgt_frm 7 rx_bytes 16493 rx_dup 1
    tx_data_frm 124 tx_mgmt_frm 9 tx_bytes 26648
    tx_assoc 1 tx_auth 1
    good_tx_frms 133 good_rx_frms 141 tx_retries 41
    tx_rate 39000 tx_kbps 8616
    tx_per 40 ack_rssi 22 rx_rssi 21

A "good" client connection should have PER (packet error rate) < 10%, and RSSI - PER >= 25.

User number one has a strong RSSI of 41 and no PER, equals a good connection.

User number two has only 21 RSSI (may be greater distance from AP), and a PER of 40 (bad, indicates
an interference source near to this client). These stats also show more retries by user number two.

Re: Calculate drop rate for individual user on ZD ?

karl_lavender — Wed, 16 Mar 2016 01:30:45 GMT

Thanks Michael. Is that tx_per stat just a percentage ? i.e. your example, user two shows a 40% error rate ?

Also your statement of RSSI - PER >= 21... would I be right in assuming user two having 21 - 40 = -19 being a horrible connection ? Or is anything <25 on that calculation going to be generally horrible ?