The manual on this CLI comand seems to be outdated. "show ap arm neighbors" gives the following fields:
bssid essid channel rssi tx-power PL (dB) AP Flags Last Update (Total updates)
I'm guessing "PL" might stand for "Path Loss"? How is it calculated?
Also I think it's safe to assume that the "tx-power" is that of the neighbor, taken either OTA in an IE or taken from the controller radio db, and that RSSI is the local RSSI and not from a remote-side value from an OTA IE, correct?