Wi-Fi 7：とどまるべきか、行くべきか

Although many amendments followed 802.11a, few were as well known as the common PHY rate amendments (802.11a/b/g/n/ac/ax). The Wi-Fi world celebrated two important innovations in a short time: Wi-Fi 6 (802.11ax) gave us OFDMA¹ and, shortly after, a whole new spectrum became available—the 6 GHz band.

The full effect of the 6 GHz band will vary² depending on where you’re sitting; however, no matter how much spectrum was released for your area, this is a HUGE deal. As Wi-Fi has grown in popularity and transitioned from a “nice-to-have” to a “must-have” service, Wi-Fi professionals have struggled to fit this increasing demand into a spectrum allotment that was set before most people had internet in their houses—much less, wireless internet. 2021 saw the first hardware released that supported all three bands: 2.4, 5, and 6 GHz.

The additional spectrum is a monumental achievement, yet it didn’t take long for Wi-Fi professionals to look forward. The next question that came up was, “What about Wi-Fi 7?”

Wi-Fi 6E or Wi-Fi 7?

The best way to answer this is to look at the many differences in the two protocols. The three biggest are the change in theoretical maximum speed, increased channel width, and the QAM.

First, the speed difference. Wi-Fi 6 maximum speed is 9.6 Gbps (which, honestly, is fast), while Wi-Fi 7 is expected to have a maximum speed of 46 Gbps. That’s 46 Gbps for a single client. That’s reaching the plaid range³ on the speedometer.

Next is the increase of channel widths. When people don’t have enough resources to accomplish tasks, they say, “We don’t have enough bandwidth to accomplish that.” Stolen directly from wireless, we now have more bandwidth to move more data. The maximum channel bandwidth in the 5 GHz band was 160 MHz wide, but, with the new spectrum in the 6 GHz band, that’s increasing to a channel bandwidth of 320 MHz wide. For reference, the entire 2.4 GHz band is only 83 MHz wide, so this is a huge increase.

Last is the increase in QAM. Quadrature amplitude modulation is the technique of encoding data on a radio signal. Wi-Fi 6 has 1024-QAM and Wi-Fi 7 is expected to be 4096-QAM. If TVs can be 4K, why not Wi-Fi? This new QAM rate, combined with the 320 MHz wide channel, makes it possible to achieve 46 Gbps.

As for similarities, both include the 6 GHz band, have really fast speeds, and have really wide channels. Also, both have few to no client devices to use all these new developments. For the average network, it’s hard to beat a well-designed Wi-Fi 6 network with quality hardware.

I know I’m throwing many numbers at you, but there’s a good reason. In Wi-Fi, speed is often the primary number that drives people to the newest technology, but it comes with a cost. That cost isn’t just the dollars spent. It’s also the requirements to get that sexy number of 46 Gbps.

Unfortunately, only one person can answer the question, “Do I buy Wi-Fi 6E or wait for Wi-Fi 7?” and it isn’t me. Not to point the finger, but only you can answer that question.

To achieve those crazy-fast rates, many things need to fall into place. In the real world, that’s not always feasible. Humans can build a car that will break the sound barrier, but it’s not an innovation you or I can use to go grocery shopping with.

As sexy as it sounds to move data at 46 Gbps, it’s not something that’s useful in 99.9 percent of Wi-Fi applications. To give you an idea, check out this website that has a table of possible data rates: https://mcsindex.net/. That’s a lot of variables across the top and down the side just to get to 9.6 Gbps. If those variables were to shift, your speed would shift, too. Now, imagine what that table would look like for a speed five times faster.

It comes down to one question

I’ve said this before, and I’ll continue to say it. The decision of whether to move to the latest and greatest technology hinges on a single question: “What’s your organization’s goal?”

If you are one of those who love to remain on the “bleeding edge” of the technology without any budget constraints then by all means, go ahead and upgrade to Wi-Fi 6E now and two years later, embrace Wi-Fi 7.

However, if you are among the vast majority who tries to optimize their IT budget then ask yourself this question – “Where are you in the budget cycle?”

If 2022 is the year to upgrade the Wi-Fi network—and your organization enjoys being a technology leader—then Wi-Fi 6E is the answer. If you crave a little more stability, opt for the current Wi-Fi 6 technology. If your turn for budget allocation isn’t for another couple of years, then wait for Wi-Fi 7.

While Wi-Fi 6E is enticing, it has a few bugs that need to be ironed out. The industry expects those growing pains to be felt with Wi-Fi 6E so that, when Wi-Fi 7 is expected to hit the market in 2024, it will be primed and ready to go.