Looking to have that Wi-Fi 6 explained properly? You’re at the right place. This wireless standard’s first routers became available on the market in early 2019 — mine was the Asus RT-AX88U. It’s time to get it sorted out.
Wi-Fi 6 has proved confusing from the get-go, especially if you want to match a router’s marketing specs and what it can realistically deliver.
In this post, I’ll try to explain all about Wi-Fi 6 and possibly a bit more. By all, I mean just the parts that matter, not the technical details or the marketing hypes. Already in the know? This post is a good refresher.
Dong’s note: I first published this piece on January 10, 2019, and updated it on April 29, 2020, with additional relevant information, including a brief section on Wi-Fi 6E.
Wi-Fi 6 explained: What is it exactly?
It’s a new and trendy name and a great idea, coined by the Wi-Fi Alliance in late 2018, for us to call what otherwise is known as the 802.11ax Wi-Fi standard.
The 6 designation is numerical — it’s the 6th generation of Wi-Fi. For the same token, tracking backward, we have 802.11ac as Wi-Fi 5, 802.11n as Wi-Fi 4, and so on. There will likely be Wi-Fi 7 in the future.
The new naming convention goes back only to Wi-Fi 4 (802.11n) because previous standards are largely obsolete. In other words, don’t bother with Wi-Fi 3, Wi-Fi 2, etc.
How fast is Wi-Fi 6?
The speeds of Wi-Fi 6 have been a big hype, and there’s a large gap between the theoretical and the real ones. And it can be confusing, too. Make sure you take your time in this part.
To know a Wi-Fi connection’s real-world speed, we need a broadcaster (like a router) and a client (like a laptop). Both have to be of the same standard and performance tier, determined by the number of streams a single Wi-Fi band can handle.
Quad-stream vs. dual-stream
So far, there have been many Wi-Fi 6 broadcasters, with new ones coming once every few months.
They include quad-stream (4×4) routers, such as the Netgear RAX200, Asus RT-AX89X, TP-Link AX6000, and mid-tier dual-stream (2×2) broadcasters, like the Netgear RAX40, TP-Link Archer AX3000, or Asus RT-AX3000. In the future, there might be Wi-Fi 6 routers with even higher specs.
On the receiving end, though, we’ve had only dual-stream (2×2) devices — like the Intel AX200 adapter card. As a result, for now, 2×2 speeds are the best we can get out of Wi-Fi 6.
And it will be a long while before you find 4×4 (or faster) Wi-Fi 6 clients. That’s because 2×2 is already plenty fast. Most importantly, this tier has the right balance of wireless speeds and energy consumption and is the most suitable for mobile devices.
A new height of base wireless speed
Generally, on the 5GHz frequency band, Wi-Fi 6 has a base speed of 1.2 Gbps (1200 Mbps) per stream. Hence, a 2×2 connection has a ceiling speed of 2.4 Gbps, and a quad-stream one tops at a whopping 4.8 Gbps.
The 2.4GHz band of Wi-Fi 6 has a base speed of about 288Mbps per stream on paper and tends to be quite slow in real life. In fact, its real-world speed is about the same as that of Wi-Fi 4 — there’s no 2.4GHz in Wi-Fi 5.
In the world of wireless data transmissions, the real-world sustained rates are always much lower than the ceiling, theoretical ones. And that’s also the case with Wi-Fi 6.
So far, most Wi-Fi 6 routers I’ve reviewed can deliver sustained speeds of around 1Gbps when used with a 2×2 Wi-Fi 6 client. So tier-by-tier, Wi-Fi 6 can provide up to about three times the speed of Wi-Fi 5.
Most of the time, though, you should expect about 50 percent improvement due to different factors. And no, Wi-Fi 6 is not necessarily always faster. Indeed, a top-tier Wi-Fi 5 connection can be speedier than a mid-tier Wi-Fi 6.
Wi-Fi 6 speeds and DFS channels: The devil is in the details
The rates mentioned above — 2.4 Gbps for a dual-stream and 4.8 Gbps for a quad-stream — only apply when the devices connect using a 160MHz channel. As the number suggests, this is an extensive channel that encompasses multiple narrower ones.
Available on the 5GHz frequency, these 160MHz channels are unique since there are just a few of them across the entire band, and all require the Dynamic Frequency Selection (DFS) spectrum.
DFS shares airspace with radar and always takes the back seat. Specifically, a Wi-Fi broadcaster automatically switches its DFS channels or moves to a narrower channel width when radar signals are present. This will cause brief disconnections or the fact devices can’t connect at top Wi-Fi speeds.
By the way, many existing clients (Wi-Fi 5 and older) don’t support DFS, though all Wi-Fi 6 ones do.
Extra notes on the 5GHz band of Wi-Fi 6: DFS and 160MHz channel width
When customizing a Wi-Fi 6 broadcaster’s Wi-Fi setting, you can’t pick a 160MHz channel as a whole. Instead, you can only pick a base channel (generally a 40MHz or 20MHz one). The hardware will automatically add contiguous extension channels on either side of the base to form a 160MHz channel.
When you force a router to use the DFS channels, such as when you set it to operate in the 160MHz channel width, it will take a longer time — between 1 and 10 minutes — to initiate its DFS-related 5GHz band. The exact wait time depends on your environment and equipment.
Consequently, you’ll notice that your high-end Wi-Fi 6 router might take a long time to boot up or apply certain Wi-Fi settings, resulting in the band appearing unavailable — the 5GHz Wi-Fi network is not there, or you can’t connect to it.
Keep this in mind when you’re tweaking your network. Patience is a virtue.
In short, the 160MHz channel width is premium real estate that’s generally not ideal for those living close (within tens of miles) to an airport or a weather radar station — every big city has at least one of those.
The use of sub-160MHz channels
For backward compatibility, hardware constraint, and oftentimes stability, Wi-Fi 6 also uses narrower channels, including 80MHz, 40MHz, and 20MHz.
Many routers, such as the AmpliFi Alien, don’t even support the 160MHz channels, partly to avoid the need for DFS channels and the potential sporadic disconnections. In fact, you should expect your Wi-Fi 6 router to use the 80MHz channel width most of the time.
In this case, the speed will reduce accordingly by a factor of two. For example, via an 80MHz channel, a 2×2 Wi-Fi 6 connection now caps at 1.2Gbps or 600Mbps per stream, or about 50 percent faster than Wi-Fi 5’s 433Mbps.
So, again, here’s an interesting fact: Quad-stream (4×4) Wi-Fi 5 devices, which have a cap speed of 1733 Mbps in 80MHz, actually deliver faster real-world speeds than 2×2 Wi-Fi 6 counterparts using the same channel width (1.200Mbps).
(I’m talking about general base standard here. Many special QAM-related techniques can increase Wi-Fi speeds in theory when compliant devices are used exclusively together.)
The marketing ploys
So, the lack of support for the 160MHz channel bandwidth is generally not necessarily good, but networking vendors have figured out a way to make it sound good.
Quite creatively, they call their 80MHz-at-best Wi-Fi 6 routers 8×8 ones (instead of 4×4). Because 8 x 600 = 4 x 1200. Got it? The problem is there are no 8×8 clients.
(Again, technically, things are more complicated than that. For example, if clients of different tiers all used the 80MHz channel width, these 8×8 routers might have some advantages since they are geared toward this configuration. Realistically, the Wi-Fi airspace is anything but conforming, and you always have clients using different channel widths.)
Another thing with Wi-Fi 6 is that we now have routers that use different Wi-Fi tiers and standards for each band. The Asus RT-AX92U, for example, is a tri-band Wi-Fi 6 router that has one 2×2 2.4 GHz Wi-Fi 4 band, one 2×2 5 GHz Wi-Fi 5 band, and another 4×4 5 GHz Wi-Fi 6 band.
Networking vendors add up all these bands’ streams into a single (large) number for marketing purposes. Asus calls the RT-AX92U an 8-stream (8×8) router. Furthermore, they combine the bandwidth of all of the router’s bands into a single (huge) number. As a result, you’ll find AX6000, AX11000 routers, and so on.
That said, these numbers only mean the potentials collective bandwidth of a router when all of its bands are used. Since a Wi-Fi connection takes place on a single band at a time, the fastest band of a router determines its cap speed, not its bands or their total number of streams.
So, the Asus RT-AX92U above is a 4×4 Wi-Fi 6 router that can deliver up to 4.8 Gbps to a 4×4 client or 2.4 Gbps to a 2×2 client.
And that’s only true when it works as a single router with a single client. That’s because a Wi-Fi router shares its wireless bandwidth between connected clients. (By the way, in a wireless mesh installation, the RT-AX92U is actually just a 2×2 Wi-Fi 5 solution.)
Wi-Fi 6 speeds are a complicated matter
To deliver real Wi-Fi 6 speeds, the router needs to have at least one multi-gig LAN port. Otherwise, the Wi-Fi connection’s real-world speed will cap at 1 Gbps, no matter how fast its wireless rate can be.
That’s because, in a wireless-to-wireless connection, where you transfer data from one Wi-Fi device to another, again, the router shares its bandwidth accordingly. For example, when you copy data between two 2×2 (2.4 Gbps) Wi-Fi 6 devices using the same band, the speed between them will cap at just 1.2 Gbps.
So, a good Wi-Fi 6 router, strictly in terms of speeds, needs to have 4×4 specs (or higher) on a single band, a couple of multi-gig network ports. Most importantly, it needs to support the venerable 160MHz channel bandwidth.
And that brings us to a new and potentially exciting version of Wi-Fi 6, the Wi-Fi 6E.
Wi-Fi 6 speeds compared with older standards
|Common Name||Standard||Availability||Top Speed per Stream||Operating |
|Security Protocol||Frequency Bands||Status|
|N/A||802.11g||2003||54Mbps||20 MHz||Open |
or Wireless N
|60 GHz||Limited Use|
Wi-Fi 6E: The answer to spectrum shortage
In early 2020, the Wi-Fi Alliance introduced the Wi-Fi 6E terminology to call Wi-Fi 6 devices capable of working on the new 6 GHz frequency band.
The purpose of Wi-Fi 6E is to address the spectrum shortage — you’ll get more natural 160MHz channels out of the new frequency.
Wi-Fi 6 vs. Wi-Fi 6E
Initially, Wi-Fi 6 is available in the traditional 2.4 GHz and 5 GHz bands. With the use of the extra-wide 160MHz channels, 5 GHz runs out of space fast.
The 6 GHz frequency band addresses this shortage by providing more contiguous spectrum blocks. Specifically, using this band, Wi-Fi 6E-capable devices will have access to an additional fourteen 80MHz channels or seven 160MHz channels. None of them is part of the DFS spectrum.
Wi-Fi 6E devices will not need to resort to narrow channels and therefore can consistently deliver true Wi-Fi 6 speeds mentioned above.
There are catches
But you won’t get too excited when you’re aware of Wi-Fi 6E’s innate shortcomings.
First of all, the 6 GHz frequency has a shorter range than 5 GHz (which has a significantly shorter range than 2.4 GHz.) And, most importantly, it also requires support from the client side to work. As a result, you will need to get new hardware entirely.
So the move to Wi-Fi 6E will be expensive if you decide to do so just for the hell of it. For more, I detailed Wi-Fi 6E in this post.
Will I be able to download a movie much faster with Wi-Fi 6?
Not necessarily! Here’s why: Downloading a movie (or Netflix streaming for that matter) depends on the Internet speed, which has little to do with Wi-Fi. They are two different things.
Wi-Fi is the alternative to network cables — it allows for a local network without wires. So, the increased speed of Wi-Fi 6 (or any Wi-Fi standard for that matter) is only meaningful locally, within your home or office.
In other words, assuming all of your devices are Wi-Fi 6-enabled, you’ll be able to print, perform network Time Machine backups, or stream from a local NAS server, etc., much faster.
As for the Internet, most residential broadband services currently offer speeds significantly below that of Wi-Fi 5, which is already plenty fast. Consequently, if you use Wi-Fi 6, you’ll experience no improvement at all in Internet access.
In networking, the final speed of a connection is always that of the slowest party involved. Right now, in most cases, the Internet is that party.
It’ll be a few years or even a decade — when 5G cellular and Gigabit-class broadband are ubiquitous — before we need Wi-Fi 6 to deliver the Internet in full. But then, remember that your client needs to support the same Wi-Fi standard to get the fast speed out of a router.
Apart from higher speed caps, what else makes Wi-Fi 6 better than Wi-Fi 5?
Efficiency. Wi-Fi 6 features orthogonal frequency-division multiple access (OFDMA).
In a nutshell, Wi-Fi 6 can slice its wireless signals into many perfectly sized chunks and, therefore, can simultaneously feed more clients of different Wi-Fi specs and keep them all happy — without slowing down, that is.
Potentially, Wi-Fi 6 can maintain fast individual connections even in a crowded air space, with many clients.
Extra: MIMO vs. MU-MIMO vs. ODFMA
You might have heard of MIMO (multiple inputs, multiple outputs) and MU-MIMO (multi-user MIMO), which are other techniques of increasing Wi-Fi efficiency.
It’s quite hard to explain MIMO, MU-MIMO, and ODFMA without invoking technical jargon. That said, let’s go with this analogy. Imagine a Wi-Fi band is like a freeway; then channels are lanes applicable to different vehicle types.
We’d have the following:
- MIMO is when you use multiple trucks of the same size, no matter what the load is. That’s better than using just a single vehicle that has to go back and forth, but not great since you always have to use large trucks to make sure you can take care of any load.
- MU-MIMO is when you use multiple vehicles of different types depending on the load’s size or type. So you use a pickup truck for a big-screen TV, but just a scooter when you need to pick up a letter. All Wi-Fi 6 routers support MU-MIMO, by the way.
- ODFMA is when you cut a load of any type or size into small standard pieces that can fit perfectly in any vehicle.
Note that none of these techniques increase the bandwidth of a Wi-Fi band. They only help it work more efficiently, especially in a mixed environment, where devices of multiple Wi-Fi standards and speed grades are present.
Thanks to the use of more advanced quadrature amplitude modulation (QAM) — the way radio frequencies are manipulated — Wi-Fi 6 has much higher ceiling speeds than Wi-Fi 5.
So, ultimately, Wi-Fi 6 beats Wi-Fi 5 in speed.
How about battery life?
Battery life applies mostly to the client-side. And yes, Wi-Fi 6 clients will generally get better battery life. That’s partly thanks to the higher speed — a client will take much less time than older Wi-Fi standards to deliver the same amount of data, hence using less energy.
However, what significantly helps reduce energy use is Wi-Fi 6’s new feature called target wake time (TWT). TWT automatically puts the Wi-Fi adapter into sleep mode when it’s idle, no matter how brief, and wakes it back up when need be.
This method is similar to making a car automatically shut down its engine at a traffic stop and instantly start up when you hit the gas (which is somewhat annoying at first, but you’ll get used to it.)
Does Wi-Fi 6 have better range?
However, if you get a Wi-Fi 6 mesh system, it’s a different story. In this case, thanks to faster speeds, you can place the hardware units significantly farther away from one another (than those of Wi-Fi 5) and still get the final Wi-Fi speed fast enough for almost any application at hand. (It’s a matter of degrees here.)
Indeed, the purpose-built tri-band Wi-Fi 6 mesh systems I’ve tested all delivered exceptional Wi-Fi coverage. Examples of these are the ARRIS mAX Pro, the Netgear Orbi RBK82, or the Ubiquiti Alien Kit.
In other words, Wi-Fi 6’s fast ceiling speed compensates for the signal loss and overheads in the wireless connection between hardware units. As a result, you’ll still get fast connection speed at the far end.
So yes, Wi-Fi 6 works well for wireless mesh Wi-Fi systems, much more so than does Wi-Fi 5.
Do existing Wi-Fi clients work with Wi-Fi 6?
The short answer is yes, Wi-Fi 6 is backward compatible and will, in theory, support all existing Wi-Fi clients. In reality, it’s a bit more complicated.
Due to other requirements, such as security, efficiency settings, channel width, and so on, many existing clients will need new software drivers to work (well) with Wi-Fi 6 routers.
And for those that are too old, such as 802.11g, 802.11a, or even some 802.11n (Wi-Fi 4) clients, chances are there won’t be new drivers for them.
Also, Wi-Fi 6E will only work with Wi-Fi 6E-capable clients. It will not work with legacy clients (Wi-Fi 5 and older) at all. But all Wi-Fi 6 routers will include a 2.4 GHz band that works with all existing clients on the market.
For the most part, you can set your Wi-Fi 6 router to work in a compatible mode. However, in this case, it won’t deliver fast speeds to Wi-Fi 6 clients. It’s a bit of a dilemma.
In my testing, legacy devices proved to work better (had faster Wi-Fi speeds) when working legacy routers than with Wi-Fi 6 routers. This is especially true when you use the 2.4GHz frequency band, of which Wi-Fi 6 is indeed slower than Wi-Fi 4 stream by stream.
Should I buy a Wi-Fi 6 router?
Yes, if you have mostly Wi-Fi 5 and Wi-Fi 6 clients. You can upgrade many existing computers to Wi-Fi 6, by the way.
Wi-Fi 6 routers have more than just Wi-Fi speed. These routers tend to be beefy devices with more useful features.
But Wi-Fi 6 is not a must-have, either, and will be so in years, especially the new Wi-Fi 6E. For most of us, a good Wi-Fi 5 router will work just fine. You can find more reasons to keep using the old standard in this post.
So, if you need a new router, well, chances are it’s sensible to start with a Wi-Fi 6 one. But a Wi-Fi 5 will do, too. It’ll work with your Wi-Fi 6 devices anyway.
Wi-Fi 6 Explained: The takeaway
Wi-Fi 6 is indeed significant in terms of efficiency and speed. But it also pushes the envelope hard on the 5GHz frequency band. And then Wi-Fi 6E requires totally new hardware, which is far from ideal in terms of adaptation.
My guess is it will take Wi-Fi 6 clients a few more years to become as popular as their Wi-Fi 5 counterparts. And then it’ll require even more years for us to have real needs or the full experience of Wi-Fi 6.
The move to Wi-Fi 6 is inevitable, but it will take a while. It’s a gradual process. In the meantime, in most cases, there’s no need to ditch your Wi-Fi 5 equipment deliberately.