Finding it increasingly difficult to avoid bottlenecks though. Even with wifi 7 I still get 1.3 on my mac and 0.5 on iphone. More than enough realistically, but upstream internet is 1.7 so tiny bit unfortunately
Think I'm just going to wire the place with 10 gig fiber
>The speed advantages that Access Points have over mesh systems will become much more obvious with Wi-Fi 7.
From what I've read mesh devices generally can detect when they've got wired backhaul so they can stay in mesh mode for the clean handovers while not relying on it for actually moving data
My house is built out of reinforced concrete, so wireless signals reach almost nowhere. I got Ethernet put into the living room and bedroom and put in 2.5 Gbps USB ethernet dongles on powered hubs, so when I plug into my phone/laptop to charge they get wired ethernet automatically.
I'd like to understand why the WiFi spec developed so slowly from G to N and finally to AC but now it's seems like a new version is released every other year yet many of the features/extensions are poorly implemented or have nearly 0 real world improvement.
I'm not a hardware guy, but my guess would be evolution of radio transceiver tech in the cell space drives improvements downstream in wifi. Better transceivers can pull quality signals from what was noise generations past, its not magic of course, but the speed transceivers can run over copper cable goes up similarly. 1Gbps was a fast cable a while ago, and now we're doing hundreds of gigabits commonly.
Another thing is that features like beamforming and higher QAM, let's say, are going to matter more in ideal scenarios where APs are in their sweet spot relative to clients, and you get to take advantage of high SNRs. Is that going to help when someone buys a Netgear Wifi 7 AP only to flip it upside down behind the couch in their apartment in an environment where 2.4 and even 5 ghz are basically gone from all their neighbors' use? Still, faster data rates mean clients get on and off the air quicker overall, saving airspace and battery if applicable. So, I think there's mainstream and highly specialized features rolling out simultaneously.
Speaking just on timelines (rather than actual underlying innovations or improvements), 802.11 was in 1997, next in 1999, G in 2003, then a 6 year gap to N in 2009, 4 year gap to AC in 2013, 8 year gap to wifi 6 in 2021, wifi 7 in 2024 (though apparently buyer beware), and wifi 8 expected (according to the article) in 2028. Doesn't seem too rapid? The 8 year gap is the weird one out.
I think part of it is that if there isn't a regular and practiced process for bumping standards, then gaps between revisions can grow quite large and stagnation can set in, and if there are any significant improvements it'll take longer for them to come to fruition than if there were regular revisions that are only modest most of the time. Looking at a few other things that come to mind: USB had an 8 year gap between 2 and 3 as well, PCIe had a 7 year gap between 3 and 4 (albeit while they only had a 3 year gap between the specification for 5 to 6, it still took 3 more years (2025) for the first pcie6 devices, and I still can't buy a consumer-level pcie6 motherboard, it's a separate mess), C++ had an 8 year gap between C++03 and C++11, Java had a 5 year gap between 6 and 7 (and another 3 years after 7 to get to Java 8); all of these things now have more rapid cycles.
802.11ax introduced some changes that have real world effects: subcarrier spacing was decreased by a factor of 4. Symbol length was increased by the same factor, but that means receiver sensitivity requirements are looser for the same data rate. So, for the same signal strength you can get a higher data rate. I’ve personally seen this effect on my own phones and laptops: I get consistently higher throughput on ax networks than I do on ac.
> Wi-Fi signal strength decreases at an exponential rate as you move further away from a router.
This is surprising to me. I'd have guessed it decreases quadratically (i.e. due to the inverse square law), not exponentially.
The paragraph below seems to contain an explanation, but I don't really understand it (namely because I don't know what that percentage "Coverage" column actually means, or what we mean with "the total distance at each QAM step").
An impressive attempt to summarise Wi-Fi which is a very deep topic. However I think the executive summary already missed the most critical thing about Wi-Fi:
only 1 transmitter at a time per channel - across all WLANs, yours and your neighbours, with no deterministic way to avoid collisions.
It's a shared medium and it's not even half duplex, unlike the dedicated full duplex you would typically get with an ethernet cable to a switch port.
The fact that Wi-Fi achieves what it does with this limitation, and how it co-ordinates the dance of multiple unknown clients using the same medium - and in the presence of other RF technologies to boot - is indeed an incredible technology story, but this achilles heel is the single most defining thing about Wi-Fi performance.
> only 1 transmitter at a time per channel - across all WLANs, yours and your neighbours, with no deterministic way to avoid collisions.
That’s not correct. You and your neighbor can use the same channel at the same time. On your network, the transmissions of the other network appear will appear as noise. As long as the other devices are far enough away, however, your devices will still be able to make out their own signal.
> only 1 transmitter at a time per channel - across all WLANs, yours and your neighbours, with no deterministic way to avoid collisions.
Not true with newer standards:
> Orthogonal Frequency-Division Multiple Access (OFDMA) is a multi-user wireless transmission technology that divides a single Wi-Fi or cellular channel into smaller subcarriers called Resource Units (RUs), allowing multiple devices to transmit data simultaneously.
[…]
> Instead of one device occupying the entire channel (as in OFDM), OFDMA allows parallel transmissions. As a result, network congestion decreases significantly.
> In addition, the 802.11ax standard defines the smallest subchannel as a resource unit (RU), which includes at least 26 subcarriers and uniquely identifies a user. The resources of the entire channel are divided into small RUs with fixed sizes. In this mode, user data is carried on each RU. Therefore, on the total time-frequency resources, multiple users may simultaneously send data in each time segment, as shown in the following figure.
Today I set up a NWA210BE (Zyxel) to replace a unifi 6+ AP; I bought it second hand and my key metrics were: 4x4 MIMO, available used/discounted, current gen, fully functional standalone mode.
The 4x4 makes all the difference. Sitting in my car the 6+ would fight with my 4G for internet and cause maps to be super slow; now I'm off the property before its unusable.
I had intended to put APs in multiple rooms, but there doesn't seem like much point now.
I have a Netgear WAX218, one of the last cheap business-class APs I could find that don't require a cloud service to manage. WAY better than the pro-sumer wifi routers I was running before in access point mode. I'll have to look into Zyxel offerings a bit more when I'm ready to replace my Netgear.
What benefit does 4x4 give you? I haven't seen a single client station with more than 1x1 or 2x2. Do you have so many clients that transmit concurrently?
I've stuck with my Eero Pro 6 because it has 4x4 at 5GHz and the Pro 6E and 7 trade that for 2x2 at both 5GHz and 6GHz. The Max 7 has 4x4 on both 5Ghz and 6Ghz, but for a 3-pack for my house, the current pricing on amazon.ca is $2300, compared to the $650 I paid for the Pro 6 3-pack. (And the Pro 6 seems to have notably lower power draw than the Max 7.)
One thing that wasn't mentioned is that the more APs you have, the worst off your life gets. That's because the way clients connect to a particular AP is done client-side and you have no control over it or visibility. So, no matter how you fiddle with it, your client may connect to the AP that is 40 feet away and on another floor rather than the one that is 10 feet away with a perfect line of sight. And you won't know why. This is the problem I had with my house and had to decrease the number of APs to get over better reliability and performance.
I hate how they did this big rebrand to simplify things and then immediately ruined it with 6e and 7.
Okay, we have wifi 6, now we're adding 6GHz. How do you know if you have 6GHz? You check if it says 6...e. And is wifi 7 an upgrade to that? Lol who knows, depends on the individual device specs. Check if it says tri-band, that will tell you it supports 6GHz... OR that it can support two simultaneous networks on one of the other frequencies.
I recently got a Grandstream GWN7615 access point to add coverage on the other side of the house from the main router. It does not meet the minimum spec listed in this article but for more modest requirements I think it's an excellent value. You can get one for well under $100. It is WiFi 5, 3x3 MIMO, and you don't need any cloud account to manage it.
Informative page, but the most common speeds with 2x2 MIMO probably were (in Mbps):
Far (QPSK) 4(20Mhz)/5(80Mhz)/6(160Mhz)/7(320Mhz): 28.8/130/288.23/576.47
Near (64QAM) 4(20Mhz)/5(80Mhz)/6(160Mhz)/7(320Mhz): 144.4/650/1,441.17/2,882.35
Not bad for throughput increases, though most of the increases come from more spectrum, and the reliability comes from more MIMO antennas/streams. I've had WiFi 4/5 2x2 routers and something tells me I won't see much more than what's listed above for 7. Buying a 4x4 does get you a generation of throughput in advance pretty much, if you need it.
It seems the throughput has evolved over each spec but the reliability and distance hasn't, unless I'm mistaken? This is a big problem in place where concrete is used to build homes (e.g. the tropics) as the improvements to Wifi are basically not really relevant.
While it already is a very deep discussion, like most it does not discuss the latency improvement that 6 GHz Wi-Fi brings. Afaik Wi-Fi 6E 6 GHz has a latency of 5 ms and less, while Wi-Fi 6 comes with about 10 ms at 5 GHz.
With Wi-Fi 6's OFDMA handling the hidden node problem better, does it actually make a noticeable difference in dense apartment buildings? Curious if anyone has measured this in practice
Very interesting reference article -- I've learn a lot!
In case someone is interested, I got Claude to create a small Linux tool that analyze the capabilities of your WiFi adapter + the current established Wifi link, and explain each of them based on wiisfi.com: https://gist.github.com/severin-lemaignan/d3f854f6111e8275ae...
If we think about it, any WiFi adapter (in its most basic core functionality) is just the ability to send/receive radio at a specific frequency, and a modulation (send) and corresponding demodulation (receive) scheme on top of that.
If the modulation/demodulation can be handled by a DSP, FPGA or fast-enough CPU, then all that's really required to create a WiFi device is that and the radio component, and then of course, there are devices like "Cantennas" that could give increased range, although loss of omnidirectionality is the trade-off there...
Anyway, I never thought about the fact that different encoding methods are used relative to distance prior to reading this article (i.e., I learned something!) -- but it makes perfect sense now that I think about it!
36 comments
[ 0.23 ms ] story [ 52.0 ms ] threadFinding it increasingly difficult to avoid bottlenecks though. Even with wifi 7 I still get 1.3 on my mac and 0.5 on iphone. More than enough realistically, but upstream internet is 1.7 so tiny bit unfortunately
Think I'm just going to wire the place with 10 gig fiber
>The speed advantages that Access Points have over mesh systems will become much more obvious with Wi-Fi 7.
From what I've read mesh devices generally can detect when they've got wired backhaul so they can stay in mesh mode for the clean handovers while not relying on it for actually moving data
Another thing is that features like beamforming and higher QAM, let's say, are going to matter more in ideal scenarios where APs are in their sweet spot relative to clients, and you get to take advantage of high SNRs. Is that going to help when someone buys a Netgear Wifi 7 AP only to flip it upside down behind the couch in their apartment in an environment where 2.4 and even 5 ghz are basically gone from all their neighbors' use? Still, faster data rates mean clients get on and off the air quicker overall, saving airspace and battery if applicable. So, I think there's mainstream and highly specialized features rolling out simultaneously.
I think part of it is that if there isn't a regular and practiced process for bumping standards, then gaps between revisions can grow quite large and stagnation can set in, and if there are any significant improvements it'll take longer for them to come to fruition than if there were regular revisions that are only modest most of the time. Looking at a few other things that come to mind: USB had an 8 year gap between 2 and 3 as well, PCIe had a 7 year gap between 3 and 4 (albeit while they only had a 3 year gap between the specification for 5 to 6, it still took 3 more years (2025) for the first pcie6 devices, and I still can't buy a consumer-level pcie6 motherboard, it's a separate mess), C++ had an 8 year gap between C++03 and C++11, Java had a 5 year gap between 6 and 7 (and another 3 years after 7 to get to Java 8); all of these things now have more rapid cycles.
This is surprising to me. I'd have guessed it decreases quadratically (i.e. due to the inverse square law), not exponentially.
The paragraph below seems to contain an explanation, but I don't really understand it (namely because I don't know what that percentage "Coverage" column actually means, or what we mean with "the total distance at each QAM step").
only 1 transmitter at a time per channel - across all WLANs, yours and your neighbours, with no deterministic way to avoid collisions.
It's a shared medium and it's not even half duplex, unlike the dedicated full duplex you would typically get with an ethernet cable to a switch port.
The fact that Wi-Fi achieves what it does with this limitation, and how it co-ordinates the dance of multiple unknown clients using the same medium - and in the presence of other RF technologies to boot - is indeed an incredible technology story, but this achilles heel is the single most defining thing about Wi-Fi performance.
That’s not correct. You and your neighbor can use the same channel at the same time. On your network, the transmissions of the other network appear will appear as noise. As long as the other devices are far enough away, however, your devices will still be able to make out their own signal.
OFDMA on wifi7/802.11be: https://blogs.cisco.com/networking/wi-fi-7-mru-ofdma-turning...
Not true with newer standards:
> Orthogonal Frequency-Division Multiple Access (OFDMA) is a multi-user wireless transmission technology that divides a single Wi-Fi or cellular channel into smaller subcarriers called Resource Units (RUs), allowing multiple devices to transmit data simultaneously.
[…]
> Instead of one device occupying the entire channel (as in OFDM), OFDMA allows parallel transmissions. As a result, network congestion decreases significantly.
* https://www.netcomlearning.com/blog/what-is-ofdma
* https://airheads.hpe.com/blogs/antar1/2020/10/19/why-is-ofdm...
> In addition, the 802.11ax standard defines the smallest subchannel as a resource unit (RU), which includes at least 26 subcarriers and uniquely identifies a user. The resources of the entire channel are divided into small RUs with fixed sizes. In this mode, user data is carried on each RU. Therefore, on the total time-frequency resources, multiple users may simultaneously send data in each time segment, as shown in the following figure.
* https://info.support.huawei.com/info-finder/encyclopedia/en/...
* https://blogs.cisco.com/networking/wi-fi-6-ofdma-resource-un...
With a 26-Tone RU Type, nine devices can operate simultaneous in even a 20 MHz channel (eighteen in 40 MHz, etc); see Figures 2 and 3:
* https://www.mpirical.com/knowledge-base/wi-fi-6-and-ofdma
The 4x4 makes all the difference. Sitting in my car the 6+ would fight with my 4G for internet and cause maps to be super slow; now I'm off the property before its unusable.
I had intended to put APs in multiple rooms, but there doesn't seem like much point now.
I have a Netgear WAX218, one of the last cheap business-class APs I could find that don't require a cloud service to manage. WAY better than the pro-sumer wifi routers I was running before in access point mode. I'll have to look into Zyxel offerings a bit more when I'm ready to replace my Netgear.
Now every other brand is dead to me.
I've stuck with my Eero Pro 6 because it has 4x4 at 5GHz and the Pro 6E and 7 trade that for 2x2 at both 5GHz and 6GHz. The Max 7 has 4x4 on both 5Ghz and 6Ghz, but for a 3-pack for my house, the current pricing on amazon.ca is $2300, compared to the $650 I paid for the Pro 6 3-pack. (And the Pro 6 seems to have notably lower power draw than the Max 7.)
Okay, we have wifi 6, now we're adding 6GHz. How do you know if you have 6GHz? You check if it says 6...e. And is wifi 7 an upgrade to that? Lol who knows, depends on the individual device specs. Check if it says tri-band, that will tell you it supports 6GHz... OR that it can support two simultaneous networks on one of the other frequencies.
Far (QPSK) 4(20Mhz)/5(80Mhz)/6(160Mhz)/7(320Mhz): 28.8/130/288.23/576.47
Near (64QAM) 4(20Mhz)/5(80Mhz)/6(160Mhz)/7(320Mhz): 144.4/650/1,441.17/2,882.35
Not bad for throughput increases, though most of the increases come from more spectrum, and the reliability comes from more MIMO antennas/streams. I've had WiFi 4/5 2x2 routers and something tells me I won't see much more than what's listed above for 7. Buying a 4x4 does get you a generation of throughput in advance pretty much, if you need it.
In case someone is interested, I got Claude to create a small Linux tool that analyze the capabilities of your WiFi adapter + the current established Wifi link, and explain each of them based on wiisfi.com: https://gist.github.com/severin-lemaignan/d3f854f6111e8275ae...
https://www.wiisfi.com/images/wifi-phy-table.jpg
Basically, it shows how a different encoding scheme/modulation is used based on distance (1024-QAM 5/6 - BPSK 1/2) (https://en.wikipedia.org/wiki/Signal_modulation), which is interesting!
If we think about it, any WiFi adapter (in its most basic core functionality) is just the ability to send/receive radio at a specific frequency, and a modulation (send) and corresponding demodulation (receive) scheme on top of that.
If the modulation/demodulation can be handled by a DSP, FPGA or fast-enough CPU, then all that's really required to create a WiFi device is that and the radio component, and then of course, there are devices like "Cantennas" that could give increased range, although loss of omnidirectionality is the trade-off there...
Anyway, I never thought about the fact that different encoding methods are used relative to distance prior to reading this article (i.e., I learned something!) -- but it makes perfect sense now that I think about it!