RSSI vs. Signal Level

[Akif Hacinecipoglu]

Hello,

I'm trying to wrap wpa_supplicant so that I will try to manage when to
change bssid of the current network for better signal level. However,
I'm confused with RSSI and signal level values of APs.

Here's an example log. Client was connected to 2c:d0:2d:6b:94:71. In
scan results (which was triggered recently) this AP is listed with -63
signal level while (nearly at run at the same time) SIGNAL_POLL
command output shows RSSI of -89.

I was relying on scan results but obviously it is misleading and
making me assume I'm connected to AP with the best signal level while
RSSI is very low (In fact I should have roamed to 2c:d0:2d:74:ce:e1).

My questions are,
1. Is it normal to have such a difference between these two values?
(RSSI and Signal Level)
2. Which one should I rely on while judging roaming options? (RSSI
from signal poll or Signal Level from scan results)
3. Is it reasonable to replace the signal level of currently connected
AP with RSSI from signal poll and compare with other APs with signal
levels from scan results?

Thank you for your help,
Best,
Akif.

BSS: last_scan_res_used=20/64
wlo1: New scan results available (own=1 ext=0)
wlo1: Radio work 'scan'@0x55a7fd21eca0 done in 0.367635 seconds
wlo1: radio_work_free('scan'@0x55a7fd21eca0): num_active_works --> 0
wlo1: Scan results matching the currently selected network
wlo1: 2: 2c:d0:2d:6b:94:71 freq=2412 level=-63 snr=26 est_throughput=65000
wlo1: Selecting BSS from priority group 0
wlo1: 0: 2c:d0:2d:74:ce:e0 ssid='aidenWifi' wpa_ie_len=24
rsn_ie_len=24 caps=0x1431 level=-61 freq=2412
wlo1: skip - SSID mismatch
wlo1: 1: 2c:d0:2d:74:ce:e1 ssid='Andwifi' wpa_ie_len=0 rsn_ie_len=20
caps=0x1431 level=-61 freq=2412
wlo1: skip - BSSID mismatch
wlo1: 2: 2c:d0:2d:6b:94:71 ssid='Andwifi' wpa_ie_len=0 rsn_ie_len=20
caps=0x1431 level=-63 freq=2412
wlo1: selected based on RSN IE
wlo1: selected current BSS 2c:d0:2d:6b:94:71 ssid='Andwifi'
wlo1: Control interface command 'SCAN_RESULTS'
wlo1: Control interface command 'SIGNAL_POLL'

SSID Andwifi
BSSID 2c:d0:2d:6b:94:71
Key Man. WPA2-PSK
Cipher  CCMP

RSSI -89
Link speed 12
Noise 9999
Frequency 2412