Asus XT8 Wireless Backhaul - router at 160MHz BUT nodes at 80MHz

[delaveganz]

I have 4 Asus XT8's (v1) servicing my NZ home - the ZenWifi AIMesh router is running 3004.388.8_4-gnuton1.

Previously, using the official firmware 3.0.0.4.388_24709 and later the 3.0.0.4.388_24710 I noticed I couldn't get 160MHz for the wireless backhaul, but when I switch to Gnuton and set the Wireless - Professional - Region to Australia, the WIreless General - Channel Bandwidth 20/40/80/160MHz option is available on 5GHz-2.

Netspot identifies that the XT8 router is running at 160MHz but the nodes are running at 80MHz only - even if they are only 5-10 m away.

I am wondering if anyone has managed to get the nodes to run at 160MHz channel bandwidth so that they can get maximum backhaul throughput?

I have tried the nodes at official 3.0.0.4.388_24710 and also 3004.388.8_4-gnuton1 firmware. I also tried removing the nodes and adding them again.

I suspect I would need to SSH into the nodes and tweak some of the nvram settings ?

Appreciate any ideas on how this 160MHz channel bandwidth can be enabled on ZenWifi XT8 nodes.

 

[degrub]

Is there a region defined for NZ ? Or is it part of the AUS region ?
Are you near a radar active area for aircraft ?

 

[delaveganz]

Is there a region defined for NZ ? Or is it part of the AUS region ?
Are you near a radar active area for aircraft ?

No NZ in the region dropdown and ASUS routers are the same for AU and NZ market.

This is a rural area and closest airport is 45kms away.

Note I am using UNII-4 channel

 

[sfx2000]

Don't run 165 as a primary/control channel in 5GHz - there's a lot of rules around it - for example, in the US, 165 is limited to 20MHz for many devices...

 

[delaveganz]

Don't run 165 as a primary/control channel in 5GHz - there's a lot of rules around it - for example, in the US, 165 is limited to 20MHz for many devices...

Not seeing an option to use DFS channels at the moment.

 

[Tech9]

Note I am using UNII-4 channel

You are using U-NII-3 for your wireless backhaul, U-NII-4 is not available in your region, maximum channel bandwidth for 5GHz-2 radio is 80MHz. ZenWiFi XT8 supports up to 80MHz channel bandwidth on 5GHz-1 radio. You can't have 160MHz on any of the 5GHz radios. It's possible in theory with backhaul on Ch.114 (100-128), but this is also not available in your region.

 

[delaveganz]

You are using U-NII-3 for your wireless backhaul, U-NII-4 is not available in your region, maximum channel bandwidth for 5GHz-2 radio is 80MHz. ZenWiFi XT8 supports up to 80MHz channel bandwidth on 5GHz-1 radio. You can't have 160MHz on any of the 5GHz radios. It's possible in theory with backhaul on Ch.114 (100-128), but this is also not available in your region.

XT8 does support UNII-4. See https://dongknows.com/5-9ghz-wi-fi-6-explained-how-unii-4-can-be-exciting/

The UNII-3 Ch114 was not available when I was set for Australia region.
Tried changing to Default region, and I now see the UNII-3 channels. Will give it a go.

 

[Tech9]

You can't have 160MHz wide channel on any 5GHz radio no matter what some scanner application is telling you. With so called tri-band routers (in fact dual-band with split 5GHz band) it's conditional and region dependent. Mostly used for bumping specs for marketing purposes. Not guaranteed to work even in regions with Ch.114 available since it's all in DFS. In limited regions with U-NII-4 available 5GHz-2 radio can eventually use Ch.163, but no client device supports it. Dedicated wireless backhaul between routers only.

 

[Tech9]

To make it more clear:

Ch.114 is 160MHz wide and includes Ch.100-128
Ch.163 is 160MHz wide and includes Ch.149-177

This is not the control channel shown in Asuswrt GUI.

 

[delaveganz]

You can't have 160MHz wide channel on any 5GHz radio no matter what some scanner application is telling you. With so called tri-band routers (in fact dual-band with split 5GHz band) it's conditional and region dependent. Mostly used for bumping specs for marketing purposes. Not guaranteed to work even in regions with Ch.114 available since it's all in DFS. In limited regions with U-NII-4 available 5GHz-2 radio can eventually use Ch.163, but no client device supports it. Dedicated wireless backhaul between routers only.

Yes - that is my objective - get the dedicated wireless backhaul between the XT8 router and the XT8 nodes to run at 160MHz

 

[Tech9]

You can't since U-NII-4 is not available in your region. Currently US only.

Also keep in mind the wider the channel the shorter the range. You don't want your dedicated backhaul with shorter range than your main radio serving wireless clients. Doesn't make sense from practical point of view unless 5GH-2 radio in your region offers higher Tx power.

 

[delaveganz]

It looks like the Asus XT8 when running as AIMesh nodes to an XT8 router, are unable to have two-way 160MHz backhaul channels running between them.

I had 3 nodes - 1st was 3m away. 2nd was 9m away, and 3rd was 14m away. Only the AIMesh router runs at 160MHz. ALl nodes transmit at 80MHz channel width

I tried with only one node 3m away and same result.

Tried previously with UNII-4 Ch.149-177, and now this is the result with UNII-3 Ch.100-128.

Is this expected behaviour, or is there some nvram settings I need to apply via SSH onto the nodes?

Note I am using 3004.388.8_4-gnuton1 on the XT8 ZenWifi router and 3.0.0.4.388_24710 on the XT8 nodes.