Requirement:1. We need an AP which support all three channel widths 20, 40, 80 Mhz. Any 802.11 AC capable AP should do.
2. We need a controller which can run Aruba OS 6.4 to bring up that AP. For this example, we will use Aruba 3000 series controllers.
Solution:We can change the channel width for an AP group through arm profile. In an arm profile, we can allow / dissallow 40, 80 Mhz channel widths:
(Aruba3600) # show rf arm-profile default
Adaptive Radio Management (ARM) profile "default"
-------------------------------------------------
Parameter Value
--------- -----
Assignment Single-band
Allowed bands for 40MHz channels a-only
80MHz support Enabled
For example, to force 20Mhz, we need to configure the following:
(Master) (config) #rf arm-profile default
(Master) (Adaptive Radio Management (ARM) profile "default") #no 80MHz-support
(Master) (Adaptive Radio Management (ARM) profile "default") #40MHz-allowed-bands none
The drawback with above is that all the SSIDs on the same AP will carry that configuration. We cannot configure this on per-SSID basis from arm-profile.
To configure the same, we need to use ht-ssid-profile in SSID profile.
Configuration:
We will create three SSIDS named as per the channel widths:
1. SSID 20Mhz:
a. Create a high throughput SSID profile and disable 40, 80 Mhz channel widths:
(Master) # config t
(Master) (config) #wlan ht-ssid-profile 20Mhz
(Master) (High-throughput SSID profile "20Mhz") #no 80MHz-enable
(Master) (High-throughput SSID profile "20Mhz") #no 40MHz-enable
(Master) (High-throughput SSID profile "20Mhz") #exit
b. Create a SSID profile and map that ht SSID profile:
(Master) (config) #wlan ssid-profile 20Mhz
(Master) (SSID Profile "20Mhz") #essid 20Mhz
(Master) (SSID Profile "20Mhz") #ht-ssid-profile 20Mhz
(Master) (SSID Profile "20Mhz") #exit
c. Map the same to a Virtual AP:
(Master) (config) #wlan virtual-ap 20Mhz
(Master) (Virtual AP profile "20Mhz") #ssid-profile 20Mhz
(Master) (Virtual AP profile "20Mhz") #exit
d. Map the virtual AP to an AP group:
(Master) (config) #ap-group default
(Master) (AP group "default") #virtual-ap 20Mhz
2. SSID 40 Mhz:
(Master) # config t
(Master) (config) #wlan ht-ssid-profile 40Mhz
(Master) (High-throughput SSID profile "20Mhz") #no 80MHz-enable
((Master) (High-throughput SSID profile "20Mhz") #exit
b. Create a SSID profile and map that ht SSID profile:
(Master) (config) #wlan ssid-profile 40Mhz
(Master) (SSID Profile "20Mhz") #essid 40Mhz
(Master) (SSID Profile "20Mhz") #ht-ssid-profile 40Mhz
(Master) (SSID Profile "20Mhz") #exit
c. Map the same to a Virtual AP:
(Master) (config) #wlan virtual-ap 40Mhz
(Master) (Virtual AP profile "20Mhz") #ssid-profile 40Mhz
(Master) (Virtual AP profile "20Mhz") #exit
d. Map the virtual AP to an AP group:
(Master) (config) #ap-group default
(Master) (AP group "default") #virtual-ap 40Mhz
3. SSID 80 Mhz. Aruba default configuration will create an SSID with channel width 80 Mhz. Thus we will add default virtual AP profile, and SSID profile with the essid changed:
a. Create a SSID profile and map that ht SSID profile:
(Master) # config t
(Master) (config) #wlan ssid-profile default
(Master) (SSID Profile "20Mhz") #essid 80Mhz
(Master) (SSID Profile "20Mhz") #exit
c. Map the same to a Virtual AP:
(Master) (config) #wlan virtual-ap default
(Master) (Virtual AP profile "20Mhz") #ssid-profile default
(Master) (Virtual AP profile "20Mhz") #exit
d. Map the virtual AP to an AP group:
(Master) (config) #ap-group default
(Master) (AP group "default") #virtual-ap default
Verification
We can verify the config:
(Aruba3600) #show ap bss-table
Aruba AP BSS Table
------------------
bss ess port ip phy type ch/EIRP/max-EIRP cur-cl ap name in-t(s) tot-t mtu acl-state acl fm
--- --- ---- -- --- ---- ---------------- ------ ------- ------- ----- --- --------- --- --
9c:1c:12:8a:2e:40 80Mhz N/A 10.1.1.254 g-HT ap 1/21/21 0 9c:1c:12:c0:a2:e4 0 38m:36s 1500 - 2 T
9c:1c:12:8a:2e:41 40Mhz N/A 10.1.1.254 g-HT ap 1/21/21 0 9c:1c:12:c0:a2:e4 0 29m:15s 1500 - 2 T
9c:1c:12:8a:2e:42 20Mhz N/A 10.1.1.254 g-HT ap 1/21/21 0 9c:1c:12:c0:a2:e4 0 26m:54s 1500 - 2 T
9c:1c:12:8a:2e:50 80Mhz N/A 10.1.1.254 a-VHT ap 48E/21/21 0 9c:1c:12:c0:a2:e4 0 38m:36s 1500 - 2 T
9c:1c:12:8a:2e:51 40Mhz N/A 10.1.1.254 a-VHT ap 48-/21/21 0 9c:1c:12:c0:a2:e4 0 29m:15s 1500 - 2 T
9c:1c:12:8a:2e:52 20Mhz N/A 10.1.1.254 a-VHT ap 48/21/21 0 9c:1c:12:c0:a2:e4 0 26m:54s 1500 - 2 T