In my home, on 5 GHz I tested 20 MHz bandwidth instead of 80 MHz for one week and, unless transferring big files, I couldn't notice a performance difference. I noticed slightly better stability at the far end of the WiFi range, a bit better roaming and less battery usage on mobile devices. I had no problems streaming VR games to my Meta Quest 3.
I invite everyone to try the same and report their results.

20MHz channel, when advanced MCS schemes are used (ac/ax with decently good signal levels), can support around 100Mbps. Which is more than enough for normal interactive work. Higher throughputs are necessary, as you already determined, only when there are high volumes of data to be transferred ... and I'd try really hard to use wired connectivity in such cases.

On the other hand, given regulatory limits about Tx power which apply to total Tx power which is evenly spread over the whole used bandwidth, using lower bandwidth means having higher signal strengths. And that, in turn, ensures better wifi coverage and more stable signal near coverage edges.

So all in all your observation is consistent with what can be expected if one knows a bit of radio.

For all of my client installations I use almost exclusively 20MHz on 5GHz.
Bleeding speed is rarely needed and if they really have high volume requirements my default answer is always: plug in the cable.

At home I do use 80MHz channels but I have zero interference (advantage/disadvantage of modern construction materials, depends how you look at it )

So all in all your observation is consistent with what can be expected if one knows a bit of radio.

Ah yes, it seems you do ...

Am patiently awaiting Wifi7 which - in theory at least - should make wider channels a genuinely useful and viable thing. Until then, above 40mhz is largely self defeating in most environments and its been a horrible disservice with so many devices defaulting to 80/160mhz wide channels. It's basically a case of everyone just shout over each other and we'll probably have at least a few legible sentences in there somewhere. Unless you live on a rural property with little to no noise, it's bloody horrible that all devices seem to default to widest possible channel

40mhz is genuinely more useful than 20mhz, not so much because 150mbit/s isn't enough, but because you're probably going to get 30mbit/s in parts of your property where coverage isn't great and, and 20mhz will be delivering 10-20mbit/s which is not

Wifi7 will allow channel slicing, on paper this implies that multiple AP's with overlapping 80/160/320mhz wide channels is no big deal as they'll detect adjacent interference and 'slice out' portions of the spectrum that are largely just noise. In a perfect world with a perfect implementation this would mean you'd actually want every single AP to use 320mhz wide channels, with lots of overlap. As the entire spectrum is getting used (which means less time air time in transferring data) and its divvied up amongst whats actually useful signal to clients, and not just a load of self interference
In reality I don't think it's going to work that well (especially since anything wifi6 or earlier won't cooperate, so they need to phase out of existence) and its probably a closer to wifi8/9 days with proprietary extensions that it will do this correctly. Until then, yes stick with 20 or 40mhz and ONLY use 80mhz or wider if you effectively own the airwaves around you. Anywhere else its much the same as playing loud music, you probably deserve a brick through your window for being a nuisance

...Anywhere else its much the same as playing loud music, you probably deserve a brick through your window for being a nuisance

If only listeners to the music wouldn't use their indoor devices outdoor

Am patiently awaiting Wifi7 which - in theory at least - should make wider channels a genuinely useful and viable thing. Until then, above 40mhz is largely self defeating in most environments and its been a horrible disservice with so many devices defaulting to 80/160mhz wide channels.

wifi7 will (temporarily) resolve the issue of overlapping APs fighting for the same chunk of spectrum. But it will definitely not be ultimate solution. Due to higher frequencies (6GHz) it's range will be even less than range of contemporary wifi6 APs (which will help to decrease inter-AP interference), but otherwise it's again improved throughputs for those with strong and clear signals ... and the case of @OP doesn't fall in this category.

So I'm not holding my breathe (I'm rather plugging the wire).

Wifi7 also supports MLO (Multi-Link Operation) so unlike every prior wifi standard, it can simultaneously utilize 2.4ghz, 5ghz and 6ghz. So no it will not be 'shorter range' it will utilize any band that is useful. It may even use 2.4ghz up close for small packets like syn-ack, dhcp, VoIP traffic etc whilst simultaneously using 6ghz for raw speed. As you wander off beyond 6ghz range it will just start dropping to 5ghz or 2.4ghz

Wifi7 is a big deal, it's the first time wifi has shifted its focus away from trying to push raw speed, to instead focusing on efficient and effective use of air waves and co-existence. It far more about usability, reliability and latency.
Time will tell how well vendors implement its functionality and how well driver support is across the board, but it is the start of moving from potentially laggy unreliable high packet loss wifi networks that generate frustration, to very smooth fast seamless ones where you don't have to think about it

Think about how much better cell phones work compared to wifi. You can drive along between cities and may not ever drop a packet in your phone call, you don't notice or care that its seamlessly shifted frequencies and roamed between potentially thousands of different cells along the way. As long as you have signal you're probably fine. Wifi7 is leaning more towards that type of experience

https://www.tp-link.com/us/blog/1067/wh ... tion-mlo-/

Think about how much better cell phones work compared to wifi. You can drive along between cities and may not ever drop a packet in your phone call, you don't notice or care that its seamlessly shifted frequencies and roamed between potentially thousands of different cells along the way. As long as you have signal you're probably fine. Wifi7 is leaning more towards that type of experience

Well, I believe that the communication engineers providing the infrastructure for coverage (cell towers) are on average sightly more capable (and have the means/resources) than an average user of wi-fi and they can do more than what can be normally done at home, besides they have less walls.

It seems to me that the combination of:
1) too much traffic (own or by neighbours) on 2.4 GHz + a stupid amount of wireless iot devices or hpwever wirelessly connected devices
2) lower penetration (and still quite a few incompatibilities on some channels for many devices) on 5 GHz
3) even lower penetration on 60 GHz
4) norms limiting Tx power
5) budget constraints (it's not like most people can afford to re-cable their homes, and there is also a limit on their available budget for devices)
6) higher desired (needed?) speeds
7) insert here something else

is what is currently driving so many home users to being not satisfied with their wi-fi experience.

I think that the only solution (for new houses) is to have in each room a (relatively low powered) access point, connected via cable/ethernet to the main switch/router and connect via wire as much (stupid) iot devices as possible
.
Newer wi-fi standard may better manage the transition from one AP to the other, but if there is not (appropriate, interference free) coverage everywhere, it cannot do much.

For older houses it may be possible to replace the (if present) telephone line distribution with fiber (an ethernet cable, particularly Cat 6 or above may be too thick/stiff to be inserted in telephone line conduits).

Devices *like* (example) these, one in every room:
https://it.aliexpress.com/item/1005004644076617.html

Think about how much better cell phones work compared to wifi.

I guess I know something little about cell networks (did the optimization/troubleshooting for major MNO for more than 15 years). I can tell that post by @jclaz is spot on.

And to add: compared to cell networks, wifi networks are worse due to the fact that there are plenty of networks operating on very same frequencies. This normally doesn't happen in cell networks as MNOs get frequency bands allocated for exclusive use (and pay for this right quite a bit of money) ... so it's entirely to "in house" optimizations to make things work nicely. The problems arise near to borders of MNO coverage where same frequency band gets allocated to another MNO on the other side of that border ... in Europe this normally happens on country borders, in USA it may be state borders. Since country borders are often political entities and physics doesn't give a shit about politics, signals don't stop at borders. So it's then up to operators to play nicely not to disturb neighbour (too much) ... which in Europe works quite well except on all Italian borders :-/ The good thing is if country, bordering Italy, is at least decently hilly, so the problem goes away in a few kilometers (behind second mountain ridge), but in WiFi the problem doesn't go away, the idiot from upstairs will destroy your WiFi in your whole apartment (and there will be tens if not hundreds of idiots trying to do the same through your windows and doors).
In WiFi, every family has a kid which operates his network and doesn't give a shit about what neighbour's kid does (think 2.4GHz where optimum is 20MHz on 1/6/11 but there's always somebody operating their gear at 40MHz and on randomly chosen channel), so "over the border coordination" doesn't exist. And "the border" is usually quite close to AP so inevitably there will be interference "across the border" (in both directions).

So the big thing about Wifi7 is something in cell networks exists for the last almost 15 years: Carrier Aggregation. Yay!

About neighbours, they are often not familiar enough with the technologies, but it is not like the makers of routers/access points or the technicians do much for them.

If you think about a "normal" home it is essentially a (smaller or bigger) square (of course it depends, it can be a rectangle) subdivided in smaller squares or rectangles by walls, now common sense would make obvious (let's imagine for a moment that there were no walls or that walls were transparent to radio signals) to put a single ceiling AP (let's say a Cap Ax, if deemed as WAF compatible), omnidirectional in the middle of the outer square (crossing of diagonals) and call it a day.
It is BTW more probable that you are using your wi-fi in the middle of rooms (as opposed to a corner), so coverage of a theoretical circle inscribed in the outer square would do nicely, with maybe the exception of -say - the (stupid) smart Samsung washer and drier in the corner of the bathroom/laundry.

Yet - most commonly - the AP/router is placed in a corner near the entrance (where the ISP delivers the cable or fiber) and still has (because all devices are like that) an omnidirectional antenna.
In practice you use 90° of the signal (and have lots of connection issues in the opposite corner area of your house) while the remaining 270° are going to mess with your neighbours' wi-fi's.
So you add another AP (in another corner or near a wall), of which again you use 90° or 180° while the remaining is going on your neighbours'.

In a perfect world AP's/routers with wi-fi should have some kind of sector antennas, 90° for corners, 180° for external walls and the 360° only on ceiling devices.

As well, in condo's/apartment buildings having (still theory, in practice if you want a problem or wish to start a discussion look for common shared services) a single centralized wi-fi distribution (like a hotel) would have a much better engineered coverage and would save the users a ton of money and headaches.

I use 20MHz for 2.4Ghz and 40Mhz for 5Ghz. Gets more range and more stable speeds (but lower peak-speeds).

Think about how much better cell phones work compared to wifi.

LTE will work down to about -115 dBm RSSI and with a -10 dB of SNR.
While WiFi requires a minimum of 10 dB SNR to maintain a connection.
That's a 20 dB difference, or about 10 times the range.

So the big thing about Wifi7 is something in cell networks exists for the last almost 15 years: Carrier Aggregation. Yay!

I can't wait until my neighbor sets up his WiFi 7 AP that uses 40 MHz on 2.4 GHz, 160 MHz on 5 GHz and 320 MHz on 6 GHz, all at the same time, all bands being used together (MLO shit).
Then my second neighbor finds that his system that was perfectly functioning yesterday, needs an upgrade. So he too sets up his WiFi 7 super router on all the bands.
Then the first neighbor complains that his speed is bad, and buys a nice powerful mesh system of 4 WiFi 7 routers that combined take up the entirety of the ISM spectrum. Then complain that his speed is even worse, flashes some custom ROM and cranks the power up higher than my microwave oven. Then leaves some stupid netflix documentary of 10 hours playing over WiFi on a 8k monitor smaller than my laptop's screen and falls asleep.

A week ago he was on channel 60 (80 MHz, taking channels 52 to 64). So I took channel 36 (20 MHz) and 44 (20 MHz). Then he switches to channel 36 (what a coincidence!) as primary so I switch to channel 56 and 64. Then he switches to channel 64 as primary (another coincidence I'm sure!), so I switch to channel 100 and 108. Then he switches to channel 100 (yup totally random!) and this I discovered a few minutes ago after I had 3 disconnects in a less than one hour. Right now channels 36 to 64 are completely free. I'm going to pick channel 36 and 64, lets see what happens.

Anywhere else its much the same as playing loud music, you probably deserve a brick through your window for being a nuisance

Then the first neighbor complains that his speed is bad, and buys a nice powerful mesh system of 4 WiFi 7 routers that combined take up the entirety of the ISM spectrum. Then complain that his speed is even worse, flashes some custom ROM and cranks the power up higher than my microwave oven. Then leaves some stupid netflix documentary of 10 hours playing over WiFi on a 8k monitor smaller than my laptop's screen and falls asleep.

It gets solved in WiFi 8 I've heard...

I can't wait until my neighbor sets up his WiFi 7 AP that uses 40 MHz on 2.4 GHz, 160 MHz on 5 GHz and 320 MHz on 6 GHz, all at the same time, all bands being used together (MLO shit).
Then my second neighbor finds that his system that was perfectly functioning yesterday, needs an upgrade. So he too sets up his WiFi 7 super router on all the bands.

That's not how it is supposed to work, channel slicing (also called Punctured Transmission) is meant to resolve this problem. Unlike all previous wifi generations it will slice out interfering segments
How well it will work remains to be seen but in theory it means that yeah you actually do want to use as wide of a channel as possible, and with lots of overlap, and when the airwaves are clear it will use all of it to get the task done faster. But as interference shows up it will carve out slices of the transmission, so no your neighbors router will not be smashing out that entire spectrum. As you start to use it his will drop out portions and might only occupy 160mhz worth or less

https://www.ruckusnetworks.com/blog/202 ... 20possible.

Tarana does this to quite an effective degree with their own proprietary implementation (not wifi7), they run 2x 40mhz channels but they're not just 2 channels, they're dozens/hundreds of small channels that can all work independently for each client. So you don't even need 40mhz of clear spectrum it'll work with just a sliver if necessary and gets substantially better spectral efficiency because of it

I don't expect wifi7 will implement this particularly well so yeah it might suck initially unless it starts to become more mature and widespread, but if it means a stepping stones towards not ever caring about 'clean channels' and you can just throw an AP in anywhere and it works as best as it can with whatever is available anywhere in the spectrum, then this is a very good thing. Better than trying to shuffle dedicated channels around and wasting all of the idle air time just to try keep it 'clean'

That's not how it is supposed to work, channel slicing (also called Punctured Transmission) is meant to resolve this problem. Unlike all previous wifi generations it will slice out interfering segments
https://www.ruckusnetworks.com/blog/202 ... 20possible.

From that article I can say that puncturing will only work if the interference is happening only in a spectrum that is smaller than yours. If I'm on channel 36 of 20 MHz and you are on channel 40 of 80 MHz, then if you start transmitting before I do, I'm screwed because the airwaves will all be clear, you'll use channel 36 to 48 and due to CSMA/CA my transmission will wait. So if you never stop transmitting, I'm never going to be able to talk.
However if I start transmitting before you do, then you'll skip channel 36 and use channels 40-48 (60 MHz), until I stop transmitting and then you also start using channel 36 (80 MHz).
Thus we can see that there is an incentive to use as wide a channel as possible, wider than your neighbor.
But once everyone has the widest channel possible, we are back to the initial condition and puncturing becomes just a fad.
IMO WiFi 7 will be a disaster once everyone has it. But initially it's going to be good for those that have it and bad for those that don't.





What they should of done is implement some kind of permanent puncturing. If there is an AP on channel 36 that is using only 20 MHz, and you request 80 MHz between 36 and 48, the AP should give you only 60 MHz and skip channel 36 entirely and never transmit there, ever.
Or allow to disable CSMA/CA for those that are using a small width channel in 5 or 6 GHz. I'd use the following logic : if I'm on 5 GHz or 6 GHz, and using only 20 MHz, and I'm sharing the spectrum with only WiFi 7 or higher devices, and they are all using a higher width channel, then disable CSMA/CA.

I'm unsure if they are simplifying it down to 20mhz wide slices, or if its more granular than that and can carve out i.e. multiple individual 2mhz wide slices of the spectrum
In either case no it doesn't just screw you, your device can and will at some point transmit even if there is 100% saturation of air time (which isn't the case, there is always pauses) and the wider transmitter will see this and back off. It will not wait indefinitely

It's a step in the right direction in any case. This can and will be refined over time (it might take until wifi8/9 or proprietary extensions to become refined enough to work flawlessly) but its better this starts to get rolled out now. As right now Wifi6 and below devices do not operate like this at all and have no awareness of each other, they do just blindly wait/transmit/wait