2.4Ghz WiFi on a RT-AC86U - what are the optimal settings?

[Xboxsx4life]

Not to get off track but on Asus routers (under 5GHz pro settings), there’s MU-MIMO and then another MU-MIMO that’s combined with the OFDMA option. Is the first MU-MIMO for AC and the second one for AX? Just to clarify, I have both options disabled and I plan to keep it that way. I’m just curious why there are two different settings.

 

[Woody]

Thanks to all for your input!

I have taken the sum total of what all of you said - and it looks like we are kind of coalescing around this as a consensus.

Note: for ESP devices running Tasmota, it is recommended that the band is manually configured and NOT set to auto - due to devices not automatically recalibrating themselves (https://tasmota.github.io/docs/FAQ/#device-disconnects-from-wi-fi-often)

Enable Smart Connect	OFF
Band	2.4 GHz
Hide SSID	No
Wireless Mode	N only
Channel bandwidth	20Mhz
Control Channel	Auto initially, and then manually confirm/set for ESP devices
Authentication Method	WPA2-Personal
WPA Encryption	AES
WPA Pre-Shared Key	Strong
Protected Management Frames	Disable
Group Key Rotation Interval	3600
Enable Radio	Yes
Enable wireless scheduler	No
Set AP Isolated	No
Roaming assistant	Disable
Bluetooth Coexistence	Disable
Enable IGMP Snooping	Disable
Multicast Rate(Mbps)	OFDM 6
Preamble Type	Short (but Long could be better for IOT devices)
AMPDU RTS	Enable
RTS Threshold	2347
DTIM Interval	1 (but there is disagreement)
Beacon Interval	100
Enable TX Bursting	Disable
Enable WMM	Enable
Enable WMM No-Acknowledgement	Disable
Enable WMM APSD	Enable (there is disagreement)
Optimize AMPDU aggregation	Disable
Modulation Scheme	Up to MCS 7 (802.11n)
Airtime Fairness	Disable
Multi-User MIMO	Disable
Explicit Beamforming	Disable
Universal Beamforming	Disable
Tx power adjustment	Performance

 

[Xboxsx4life]

Those look good. Keep an eye on things for a few weeks. I had to disable WMM APSD because it caused some disconnection issues with a couple of devices, and it took a while for them to reconnect after waking up. You might not have this issue at all, but just keep an eye out for it.

Also, since you have your wireless mode set to “N only”, I’m not sure there’s any value in changing the multicast rate from the default “auto” but @sfx2000 can confirm.

 

[Woody]

Those look good. Keep an eye on things for a few weeks. I had to disable WMM APSD because it caused some disconnection issues with a couple of devices, and it took a while for them to reconnect after waking up. You might not have this issue at all, but just keep an eye out for it.

Also, since you have your wireless mode set to “N only”, I’m not sure there’s any value in changing the multicast rate from the default “auto” but @sfx2000 can confirm.

@Xboxsx4life good point. Again, I was just creating the table above, based on a perceived consensus in this forum - in which @sfx2000 said "APSD isn't a bad thing, short preambles are good, and multicast rates at 6Mbps which basically forces the basic rates to 6 and above with OFDM".

HOWEVER, I am more drawn to your viewpoint "I have that band set to N-only with short preamble. Those settings combined with DTIM 1 and beacon interval at 100ms have given me fast and problem-free connectivity across all my IoT devices" - but only because, I am running approx 20 various ESP Sonoff devices running Tasmota, and am amazed that these things work at all - so want to given them all the support possible.

 

[Tech9]

As mentioned earlier there is no best settings. It's all theory and the reality is access point, clients and environment specific. You have to be happy your RT-AC86U is still working properly. This router model has much more serious issues than the effects of APSD enabled/disabled. It is also approacing EoL.

 

[sfx2000]

Not to get off track but on Asus routers (under 5GHz pro settings), there’s MU-MIMO and then another MU-MIMO that’s combined with the OFDMA option. Is the first MU-MIMO for AC and the second one for AX? Just to clarify, I have both options disabled and I plan to keep it that way. I’m just curious why there are two different settings.

Asus could have done better here, IMHO...

Mostly because MU-MIMO (uplink and downlink) and OFDMA are really two separate functions...

 

[Xboxsx4life]

That’s what I was thinking too. Thanks.

 

[sfx2000]

As mentioned earlier there is no best settings. It's all theory and the reality is access point, clients and environment specific. You have to be happy your RT-AC86U is still working properly. This router model has much more serious issues than the effects of APSD enabled/disabled. It is also approacing EoL.

I agree...

IMHO - there's a lot of settings that are exposed that if one changes them, it can hurt more than help...

Everyone likes to have knobs and levers to tweak - but generally the defaults are pretty good as they are - pick a channel and that's about it...

 

[Tech9]

IMHO - there's a lot of settings that are exposed

Indeed. In Asuswrt way too many settings are exposed for no good reason, some do nothing and some are actually confusing because there is no dependencies and you can have Legacy B/G in General with Beamforming, MU-MIMO, TurboQAM and whatnot enabled in Professional.

 

[heysoundude]

I'm currently testing the following 2.4GHz settings on my network, OP:
OFF, disabled.

So far, no issues.

 

[Woody]

I'm currently testing the following 2.4GHz settings on my network, OP:
OFF, disabled.

So far, no issues.

You mean, that you turned off 2.4Ghz completely?

 

[heysoundude]

You mean, that you turned off 2.4Ghz completely?

yes, correct. 5GHz wireless only.

From a hardware manufacturer that markets its products as AiMesh compatible, or AiMesh as being a main feature, it makes sense: you want lots of fast APs wherever you need signal, so who cares about the extra range of a 2.4GHz band radio?

So off it went as a test, and so far, so good on my network: I've a 5GHz 802.11n link to my Media Bridged RT-n66u, and everything else wifi is 5GHz AC+ capable or wired.
The Media Bridge link speed is 450Mbps both ways, I've tweaked my AC86's 5GHz to be 40MHz wide iirc (because that's what the n66 can do), so I believe wireless-AC links can only be as fast as 866Mbps, which is WAY faster than my ISP package's 50/10Mbps. smooth, happy, cool, snappy...it's all good, both wired and wireless. I haven't been out in the yard to see if coverage is what it was before the change because it's been chilly, but I'm not overly concerned about my network reaching the street (and would rather prefer it didn't,) or the neighbours. I could easily upgrade my ISP package to a 1Gbps and I wouldn't have to change anything else. (I'm going to wait on an AX-router until the prices come down or I absolutely need one, but for right now, I'm absolutely satisfied)

Put good wifi where you use it and where it's needed and leave the rest of the airwaves/aether alone, I guess, is my/the premise rather than spraying it everywhere on the chance it might get used/be needed. Everything that doesn't move gets wired, the airwaves free up for what can't be, and the network....networks (lol) and ceases to be something to be tweaked/maintained/taken into consideration as often as some in this forum would have. Internet like air...breathe away!

 

[Tech9]

so who cares about the extra range of a 2.4GHz band radio?

@heysoundude, AiMesh is still quirky and disabling 2.4GHz band may break it in wireless configuration. I never checked the newer firmware releases, but not long ago disabling 2.4GHz on the nodes from the AiMesh screen was causing complete AiMesh lock up. The theory is one thing, but the reality is different. You have a single router only and disabling 2.4GHz radio is not a problem.

 

[heysoundude]

@heysoundude, AiMesh is still quirky and disabling 2.4GHz band may break it in wireless configuration. I never checked the newer firmware releases, but not long ago disabling 2.4GHz on the nodes from the AiMesh screen was causing complete AiMesh lock up. The theory is one thing, but the reality is different. You have a single router only and disabling 2.4GHz radio is not a problem.

Going back to the OP's top post, my suggestion wouldn't work anyway, because they have an IoT swarm that relies on it. And Yes, I'd not be surprised if my suggestion also has negative effects on AiMesh.
But now my thoughts/perspective is out there for people to take or leave, and that means they'll have to ponder on them for their own situation.

 

[Tech9]

I've tweaked my AC86's 5GHz to be 40MHz wide iirc (because that's what the n66 can do), so I believe wireless-AC links can only be as fast as 866Mbps

You don't have to do that. The max link speed is 400Mbps at 40MHz wide channel to 2-stream AC client, about 200Mbps throughput or some more. Still faster than your WAN, but hurts your WLAN speed. You may get better range with 40MHz wide channel though, about 3dBm better SNR.

 

[heysoundude]

You don't have to do that. The max link speed is 400Mbps at 40MHz wide channel to 2-stream AC client, about 200Mbps throughput or some more. Still faster than your WAN, but hurts your WLAN speed. You may get better range with 40MHz wide channel though, about 3dBm better SNR.

I did it to make sure the n66u is a happy camper, which it seems to be so far for about a week now. May not have -needed- to do it, but it seems to have kept things great or possibly made them better

 

[Tech9]

Your choice, but you have restricted your entire WLAN (all devices) to about 200Mbps throughput (combined) for one single old client. This change may make a substantial difference if you have a NAS attached to your router and transfer files locally over Wi-Fi.

 

[sfx2000]

WLAN (all devices) to about 200Mbps throughput

Going back to the origin of the thread - 200Mbit/Sec is more than enough for 2.4 in a 20MHz channel... most clients there are going to be N144 at best, N72 for single stream clients..

a 20Mhz 2.4 channel can cover a lot of range, and for many applications, this is more than enough.

 

[Tech9]

200Mbit/Sec is more than enough for 2.4 in a 20MHz channel...

@heysoundude is limiting his 5GHz throughput to AC devices for no good reason cutting the channel width from 80MHz down to 40MHz. This is not needed, both N and AC devices can coexist on 80MHz wide channel network with no issues. Obviously N devices will use 40MHz wide channel.

 

[Krzysztofz]

If I said to you that I am running an RT-AC86U in a detached house with not very thick stone walls, in an area with approx another 10 2.4Ghz networks visible from my neighbours, but very few of them on Ch11 (which I have set). This is a mixed network of 2 - 3 laptops and two smart phones (connecting at 5Ghz) and approx 30 other (mainly IOT Tasmota ESP) devices connecting on 2.4Ghz AND quite a lot of BT traffic for about 10 Xiaomi room temp sensors (all chatting to Home Assistant).

What would you suggest that I change in my current settings below?

I ask, because while a see a number of forum posts focused on certain settings, I don't think I have ever seen a conclusive best practice post that covers all 2.4Ghz settings in one.

Thanks!

​

Band	2.4 GHz
Enable Radio	Yes
Enable wireless scheduler	No
Set AP Isolated	No
Roaming assistant	Disable
Bluetooth Coexistence	Disable
Enable IGMP Snooping	Disable
Multicast Rate(Mbps)	Auto
Preamble Type	Long Short
AMPDU RTS	Enable Disable
RTS Threshold	2347
DTIM Interval	3
Beacon Interval	100
Enable TX Bursting	Enable
Enable WMM	Enable
Enable WMM No-Acknowledgement	Disable
Enable WMM APSD	Enable
Optimize AMPDU aggregation	Disable
Modulation Scheme	Up to MCS 11 (NitroQAM/1024-QAM)
Airtime Fairness	Disable
Multi-User MIMO	Disable
Explicit Beamforming	Enable
Universal Beamforming	Enable
Tx power adjustment	Performance

I had lots of connection issues on ac86u also on ax55 and ESP8266 devices and Tasmota firmware. Yesterday I try to setup another tasmota esp8266 device and I couldn't connect to network, setup Draytek router for testing, tasmota device connect without any problem. Decided to try.

- disable DHCP server on asus router
- start DHCP server on other device in my case Synology NAS

Tasmota device connected without issues.

Worth to try.