Technical Tip: BSS coloring on the FortiAP-F models

sachitdas_FTNT · ‎02-03-2023

Description

This article describes BSS coloring on the FortiAP F series.

Scope

ALL FortiAP-XXX F models platform.

Solution

For more info about BSS coloring, visit these links:

- https://docs.fortinet.com/document/fortigate/7.0.0/new-features/670582/automatic-bss-coloring-7-0-2

- https://www.commscope.com/blog/2018/wi-fi-6-fundamentals-basic-service-set-coloring-bss-coloring/

On FortiGate, automatic BSS coloring is enabled by default, when a collision is detected on FortiAP radio, it changes the color.

It is also possible to change the mode from automatic to static. In Both modes, collision detection works.

BSS Color configuration in FortiOS :

# config wireless-controller wtp-profile
edit <profile>
config <radio>
set bss-color-mode {auto | static}
end
next
end

Example : AUTO.

# config wireless-controller wtp-profile
edit FAP431F-default
config radio-1
set bss-color-mode auto
end
end

Example : STATIC.

# config wireless-controller wtp-profile
edit FAP431F-default
config radio-2
set bss-color-mode static
set bss-color 16
end
end

BSS Color config verification in FortiAP CLI :

FortiAP-231F # rcfg

.

bss color mode : static /auto

FortiOS CLI :

FGT# diagnose wireless-controller wlac -c wtp FP231FTF20004934 | grep bss
bss color mode : Static
bss color : 32 <- BSS Color code value.
base bssid : e0:23:ff:d7:82:48
bss color mode : Auto
base bssid : e0:23:ff:d7:82:50

Note: once set BSS coloring mode to static and set value to 0, which means BSS coloring is disabled.

BSS coloring status can be checked under iwpriv command:

BSS coloring disabled:

FortiAP-231F # iwpriv wifi0 g_he_bss_color

wifi0 g_he_bss_color:256 (0x100)

BSS coloring enabled:

FortiAP-431F # iwpriv wifi1 g_he_bss_color

wifi1 g_he_bss_color:21 (0x15)

FortiOS GUI WiFI Events:

- BSS Color Collision detection log:

- FortiAP Log: BSS Color Collision detection debug message:

[ 3153.712903] ieee80211_bsscolor_collision_detection_hdler BSS color collision detected on 32, entering new color selection process
[ 3153.712948] __ieee80211_select_new_bsscolor New BSS color selcted, auto = 1, old = 32, new = 16 <- when collision detected, it will change the colour.

Sniffer Capture:

Adolfo_Z_H · ‎02-21-2023

hi team, packet capture screen capture is unreadable, please enhance.

Good stuff!