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5 Things To Know Before You Buy A Draft 11ax Router
- Thread starter thiggins
- Start date
Read on SmallNetBuilder
Great article! Just shows those shrewd with their money (and reliability) should stick to existing standards. I learnt back with the draft N standard not to invest in draft standards again and whilst it may not be exactly the same now, there is next to no reason currently for me to spend anything more than a value for money AC router. 
WiFiNemesis
Regular Contributor
A veritable public service, that.
sfx2000
Part of the Furniture
good post - and folks know I have a beef with 2.4Ghz and the "extended" standards in any event...
Getting 40MHz channels in most places these days is a challenge - and getting the "extended" modulation rates like 256QAM/1024QAM is almost impossible - even if one get's a "turbo QAM" connection as some vendors suggest, it usually falls back to 64QAM and 20MHz at the end of the day...
https://www.snbforums.com/threads/vht-in-2-4ghz-ism-band-it-can-happen-proof-attached.48539/
802.11n is probably the end of days for 2.4GHz - not that it's bad, but legacy is what it is...
Achieving the maximum 1148 Mbps 2.4 GHz rate requires a device support 1024 QAM modulation, 40 MHz bandwidth and four streams, as shown in the table below
Getting 40MHz channels in most places these days is a challenge - and getting the "extended" modulation rates like 256QAM/1024QAM is almost impossible - even if one get's a "turbo QAM" connection as some vendors suggest, it usually falls back to 64QAM and 20MHz at the end of the day...
https://www.snbforums.com/threads/vht-in-2-4ghz-ism-band-it-can-happen-proof-attached.48539/
802.11n is probably the end of days for 2.4GHz - not that it's bad, but legacy is what it is...
Glad you found it interesting. You guys probably already know about what was in the post. But I hope the article has some legs beyond the SNB audience.
Next up is a look at the effect of 160 MHz networks. One source has told me 80+80 is dead for AX. The RF design is too much of a pain in the butt and costly. Contiguous 160 and DFS support will be commonplace.
Next up is a look at the effect of 160 MHz networks. One source has told me 80+80 is dead for AX. The RF design is too much of a pain in the butt and costly. Contiguous 160 and DFS support will be commonplace.
sfx2000
Part of the Furniture
Hehe... someone is going to do 80+80, just because it's in the spec, LOL... 160MHz has it's own RF challenges - not impossible, as we're seeing it now with 11ac in limited scope...
11ax, like 11ac, is fairly comprehensive, but 20 percent of the spec is where 80 percent of the real benefit is - just like in 11ac, where Wave 1 had the most impact, Wave 2 was incremental at best.
TheLostSwede
Very Senior Member
What about regions where there aren't enough channels to make up 160MHz of contiguous bandwidth? At least based on the 802.11ac channels, there are countries like Japan, China, Korea and oddly enough, Switzerland that doesn't offer any 160MHz channels and some have no 80MHz channels either. This suggests 802.11ax will have zero net benefit for those countries.
The "80+80 MHz" statement was opinion, not necessarily fact. But it was offered by someone who has access to more industry information than I have.
5 GHz (and up) spectrum expansion is going to be important for sure. It will be up to each region to fight that battle.
It may be cold comfort, but remember 11ax protocols and modulations are good for both bands. So once 11ax clients are out, operation in 2.4 may get more efficient. But with so much legacy stuff out there, it probably won't help significantly.
Then there is also bandwidth agility. 11ac is supposed to adapt bandwidth frame-by-frame. I assume 11ax will also.
sfx2000
Part of the Furniture
There can still be benefit of 11ax in 40MHz channels, similar to the benefits noted with 11ac in the same conditions.
The efficiency seen at the MAC level is not dependent on channel widths for uplink or downlink - and 11ax makes some theoretical improvements there over the 11ac and Legacy MAC's. Hopefully theory translates into practical implementation.
@thiggins - looking forward - 11ax and legacy devices and overlapping BSS's - should be opportunities for interesting test cases to see what the impact will be - little to none, or will 11ax dominate the channel to the negative impact of the legacy clients and adjacent networks, similar to previous concerns about LTE-LAA and Multifire...
Perhaps. But didn't you already say "Getting 40MHz channels in most places these days is a challenge"?
Yup. We'll be looking at this. Just waiting for real product to ship. It's gonna be later vs. sooner.
sfx2000
Part of the Furniture
In 2.4, yeah, 40MHz can be a challenge - in 5GHz, should be fairly easy, and I've seen quite a bit of 11ac 40MHz channel plans in the hospitality markets (coffee shops, hotels, etc) and enterprise.
sfx2000
Part of the Furniture
Could go either way, I'm guessing - the 11a/n/ac was fairly painless, and there, the legacy clients sometimes even saw improved performance with 11ac AP's.
Or it could be the mess that the 11b to 11g transition - where legacy 11b could seriously impact 11g BSS's
You're right. I should not have assumed you were just referring to 2.4 GHz. Yes, 40 MHz bandwidth in 5 GHz seems to be more the norm.
Do you think the average (any?) consumer will run their AX router in 40 MHz mode?
sfx2000
Part of the Furniture
Do you think the average (any?) consumer will run their AX router in 40 MHz mode?
Folks can always explore 40MHz in 11ac if the Router/AP offers the setting - can see 2 to 3 dB improvement in RSSI, and medium to long range that can be an MCS step improvement, and extend the foot print a bit.
I just want to see more flexibility on products that are actually sold by different manufacturers. Right now I have two AC routers and 1 range extender (won from a competition here on SMB) and none of them have a matching way to set 5ghz channels.
My Netgear R7000 doesn't work with valid DFS channels in the UK.
My BT supplied modem/router only has a choice of two.
My Asus range extender lets me set practically any channel.
I would love if it was just standardised and made more straightforward so it was less hassle choosing which channel, upper/down etc
Do you guys know what I mean?
My Netgear R7000 doesn't work with valid DFS channels in the UK.
My BT supplied modem/router only has a choice of two.
My Asus range extender lets me set practically any channel.
I would love if it was just standardised and made more straightforward so it was less hassle choosing which channel, upper/down etc
Do you guys know what I mean?
This situation has nothing to do with 11ax.
DFS is still not commonly supported by consumer WiFi products. It requires an extra set of testing at least in the US for separate FCC certification. Not all manufacturers want to go through that.
DFS will be pretty much required for viable 11ax products if they want to support 160 MHz bandwidth.
sfx2000
Part of the Furniture
160 is going to require some degree of DFS in pretty much all regulatory domains...
From the main site - 11ax isn't going to change that one bit...
Yeah I realise its got nothing to do with AX but I just wish there would be focus on more standardisation rather than new standards completely, if you browse several GUIs of AC routers its confusing which channels they are going to use. Its far more complicated than N where you can just choose a number, now you never know what you get when you set your AC channel when using anything other than 20mhz bandwidth.
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