What's Missing From Your Wi-Fi 6 Router? OFDMA

[MrCommunistGen]

Thank you for the enlightening article! I had assumed that OFDMA was included and enabled on all WiFi 6 routers since it was one of the key features in WiFi 6... silly me.

Not only is the feature not enabled on all the devices, I come to find that many of the devices on the market aren't even CAPABLE of OFDMA... smh

I did have one question though. I just re-read the article to make sure I didn't miss it, so forgive me if it is already stated:
Unless the router is explicitly in the table in the article, it currently has NO OFDMA support, correct?

Example: The RT-AX88U is in the table and is explicitly stated to have support for OFDMA on 5GHz. Since other "WiFi 6" routers are missing from the table entirely, like the RT-AX92U (and many others), I would assume that they currently lack OFDMA support.

As your time permits I'd love to see a followup as the situation develops, including more information (a more exhaustive list?) about which chipsets do or do not support OFDMA at a hardware level. Also waiting with bated breath to see some form of OFDMA performance testing once the ecosystem actually permits it.

Thank you again for your years of hard work!

 

[thiggins]

Correct. If a product is not in the table, you should assume OFDMA is NOT enabled.

You can be sure that you'll hear more about which products do and don't support OFDMA and more test results.

 

[Jani]

I see lot common with MU-MIMO and OFDMA. Both promises improvements to heavily crowded networks. Unfortunately home WiFi networks are not in this category. In networks of tens simultaunus users one might see some noticable improvement. But in home networks you can skip this technology as was with MU-MIMO.

 

[sfx2000]

I think the Wi-Fi industry needs to take a pause and figure out the next technology that will provide more practical benefit for most users.

It won't happen, of course, because the hype machine must be fed so consumers keep getting sucked into buying new stuff.

I agree - looking back, 802.11ac Wave1 and Mesh have probably made the most benefit to the average home...

 

[System Error Message]

can i say a coffee maker is missing from my wifi router
Google has coffee to the house

 

[iwod]

I remember we had a discussion about this on SNB sometime in 2018 or even ealier, where the Draft status was riddled with comments not fixed. And they had no intention of fixing it while trying to force their way through final draft.

I posted something similar in other forums and all I got was stop being so pessimistic. ( I call it realistic )

Everything turns out to be true. And now the cat is out of the bag, WiFi 6 will forever be a bloody pile of mess.

If it wasn't for insane patent cost, I would have much rather have NR-U or LTE-U working in unlicensed spectrum.

Edit: What about WiFi 6E, ( I hated it at first, now it seems to be the solution ), Would WiFi 6E mandate OFDMA?

Edit: 2, a little digging, it seems 160Mhz isn't mandated, and OFDMA seems to be in similar situation with WIFi 6.

 

[kc6108]

I thought the RAX120 was Wi-Fi 6 certified. I guess because of all the exposure the certification received. Its actually just Wi-Fi Certified, or Wi-Fi Certified for WPA3 if that's a thing?

 

[thiggins]

"6E" isn't a standard. It's the Wi-Fi Alliance's marketing term for 6 GHz Wi-Fi. If the spectrum is approved (the cellular industry, who have much more political clout than the WFA, are also competing for the spectrum), 11ax will be the operative standard and legacy devices will not be allowed. At least that's the current thinking.

RAX120 is not Wi-Fi 6 Certified. WPA3 Certification is separate and not included in Wi-Fi 6 Certification. Give the Wi-Fi Alliance's Product Finder a try.

 

[sanke1]

Any hopes of Asus enabling OFDMA for 2.4 Ghz on Broadcom based routers like RT-AX88U and GT-AX11000 ?

 

[thiggins]

Maybe never unless the legacy device reliability problems can be fixed.

 

[crashnburn]

They used to be around 200$ when they launched. 100$ is a pretty reasonable price if you want a capable router. You can get cheaper 30-50$ models, however the performance will be in line with their pricing. The two models I mentioned are currently the sweet spot in terms of pricing vs performance.

I am not sure if this got across -
I'll add -
I am in a 2 level Condo made of Concrete in High Concrete Urban Asian City -

I am already using Mikrotik HapLite (Wireless N) as PRIMARY ROUTER and its PERFORMANCE is more than adequate (over Cat 6).

What I need 2 devices (1 for each level) to act as "Wireless AC" Access Points
(So 100$ for each is out of budget) -
To handle the Multiple "Smart Home Devices" that are crowding my airspace.

If I was to spend that much for each Wireless AC AP - I might as well get Ubiquiti AC APs.

Trying to not spend that far for now.

I do not mind buying several cheap Wireless AC routers devices and do some Wireless AC to Wired testing (do tell me how-to) on them to pick from that list and then have to get 2 of them.
Maybe some Tenda / Xiaomi / TP-Link or Chinese Routers as APs - maybe flash them DD-WRT or Open WRT if possible, and just to be "inexpensive AC AP slaves"

Hoping to add 1/2 cheap routers as APs.
So, 40/50$ or something as cheap as 15/20$ just to act as good Wireless APs to a
Master Mikrotik HAPLite (N only) to handle Multi devices.

Also at this 69$ / sub 100 price would it make sense to there instead of 100$ WiFi 5 ones?
https://www.snbforums.com/threads/t...b-100-wi-fi-6-router.59719/page-2#post-522980

 

[sanke1]

Maybe never unless the legacy device reliability problems can be fixed.

But is the RT-AX88U hardware really capable of 2.4 Ghz OFDMA?

 

[thiggins]

But is the RT-AX88U hardware really capable of 2.4 Ghz OFDMA?

Yes. Same radio chip as 5 GHz.

 

[yenchee1970]

D'oh. iphone 11. Fixed. Thanks for the catch.

As far as we can test today, iPhone 11 seems not to support OFDMA. It is not Wi-Fi 6 certified either. By the way, iPhone doesn't support MU-MIMO for models we have on hand though the chip is capable for the feature.

 

[thiggins]

As far as we can test today, iPhone 11 seems not to support OFDMA. It is not Wi-Fi 6 certified either. By the way, iPhone doesn't support MU-MIMO for models we have on hand though the chip is capable for the feature.

How are you testing for OFDMA? In most cases you need 4 active OFDMA devices to get an AP to use OFDMA.

 

[yenchee1970]

How are you testing for OFDMA? In most cases you need 4 active OFDMA devices to get an AP to use OFDMA.

You don’t have to test 4 devices as long as you have the access of chipset command line. iPhone 11 did not declare it’s ofdma capable at all. Not sure if it will be changed in the future iOS.

 

[thiggins]

You don’t have to test 4 devices as long as you have the access of chipset command line. iPhone 11 did not declare it’s ofdma capable at all. Not sure if it will be changed in the future iOS.

A colleague told me he confirmed the iPhone 11 supports OFDMA DL only in 2.4 and 5 GHz. I have not confirmed this myself.

 

[ikjadoon]

A fantastic article. I always come to SNB to cut through the manure, the shiny manure, and the expensive manure of marketing claims. I'm not in the market now, but I like to keep up-to-date in case someone asks for buying advice.

Big props for such a clear & well-researched article. I'll be watching this space in the next few years.

Even as we now have three Wi-Fi 6 clients (one AX200, one AX201, and one iPhone 11; all stuck on 2.4 GHz due to bad house layout), I see good reason to spread the cost of my trust Synology RT2600ac out some more ($250, which still makes me wince a little). Still stunned we're seeing single routers (i.e., non-mesh) at a $400+ asking price. Just miles of diminishing returns.

 

[name99]

The OFMDA resource-scheduling problem is more or less the LTE+ cell-phone base station resource-scheduling problem, no?
Which makes me wonder what the issue is — presumably good enough algorithms exist and have been known for some time.

Could it be as simple as the vendors all cheaped out and are trying to do a quad-A72’s worth of work on a quad-A53 core and discovering, to their consternation, that there just isn’t enough CPU there to run the algorithm within the allotted time under all conditions?

 

[thiggins]

The OFMDA resource-scheduling problem is more or less the LTE+ cell-phone base station resource-scheduling problem, no?

No. The difference is in mobile networks, the network controller is the boss and devices do as they are told. In Wi-Fi, it's the opposite. This presents extra challenges due to the uncertainty of when things happen. That's one reason why the Wi-Fi industry is in a hurry to get to 6 GHz, where only AX devices will be allowed and (maybe) all traffic in a BSS (AP) can be scheduled. (Different APs sharing the same channel(s) will still need to contend for airtime, so it won't be a perfect world.)

Yes, there are probably some scheduling problems in common to both. And yes, consumer APs have less computing power and memory to use than mobile controllers.