To WiFi 6 Or Not To WiFi 6, That Is The Question

Right out of the gate, I have to admit it somewhat pains me to go with WiFi 6, but marketing is winning out. WiFi 6, otherwise known as 802.11ax, is the forthcoming next generation of WiFi, with the WiFi 6 certification path expected to be here soon.  It’s the next advancement in the wireless world, and as with basically every other past generation, someone is going to wonder: should you upgrade to WiFi 6?

At the risk of being cliché, the answer is: it depends.

If you are a home user, this might be an easier decision, at least from a purchasing perspective. Most home users are replacing a single wireless router, so it’s a matter of spending a couple hundred dollars as frequently as you wish to upgrade-at least on the networking side. For home and enterprise users, there is one thing to keep in mind, forgetting the cost of the networking gear. That is, right now, there are very few 802.11ax client devices. Samsung has a phone that includes it, and just the other day, Apple announced their own WiFi 6 capable devices. There’s a smattering of laptops and adapters, but there are still relatively few options. It’s not anywhere close to mass adoption, nor will it be for probably at least another 12-24 months-depending on how your organization functions. Speaking from experience, many companies tend to refresh enterprise hardware at a rate of every three to five years. If you just upgraded to 802.11ac gear, chances are you are going to sit the WiFi 6 cycle out.

Moving past the availability of the hardware and the budgetary constraints and purchasing cycles, is there a compelling technical reason to advocate for the adoption, whether early or not, of WiFi 6? Again, it does depend.

Unlike the last several 802.11 amendments, 802.11ax is not about speed improvements per se.  Whereas 802.11ac was hyped up as very high throughput (VHT), 802.11ax is geared toward efficiency. So, right away, we can see the appeal of the 802.11ac amendment-the sales and marketing hype was pushing it as gigabit speeds on wireless, and who doesn’t love speed? That marketing speak no doubt worked wonders to move a lot of SOHO gear (and probably a bit of enterprise gear, too). But for anyone that read the notes about the amendment, or who understands wireless technology, there was a caveat (several, actually) with the VHT. For starters, it depends on just how close to an AP and how capable your device was. Older devices? Never touching the max advertised speed. Cell phones? Generally going to be capped, too. Of course, none of that was mentioned in the sexy marketing copy. For further proof, just check out this link:

mcs index

The other, just as important note? Your 802.11ac compliant deployment would never achieve those high rates if you didn’t embrace channel bonding-that is, going with 40-, 80- or even 160-MHz wide channels. The reality is, unless you have a perfect RF environment-no neighbors and not a lot of APs, you would not go with the bonded channels. Based on anything I’ve been hearing, most enterprises stick with 20 MHz wide in order to have the full use of up to 25 non-overlapping channels. So, just like that, a lot of the perceived gains offered by 802.11ac can be nullified because in order to achieve them, a lot of things have to be done in a very particular (and not always friendly-to-others) way.

So, looking past those “speed gains”, WiFi 6 is going to be faster than ac, right? Not necessarily…or at least, that’s not it’s core intent, I’d say. 802.11ac is dubbed “high efficiency wireless”. As we all should know, WiFi is a shared medium. Think of it like a freeway: when you are the only car driving on it, you go fast and there’s no contention for the road. You get where you need to get quickly. If you drive that same freeway during rush hour, it probably takes you a lot longer, stop and go traffic and lots of contention.

empty freeway

Now, with 802.11ac, on that freeway, it was saying that IF the road was empty, you could go faster than ever before, but in order to achieve top speeds you’d have to be driving a souped-up car that took up most of the lanes at once. Highly impractical, not to mention highly unlikely.

crowded freeway

With 802.11ax, on the other hand, it’s not about an empty freeway achieved by traveling at 5 in the morning. Instead, it’s approaching things like traffic optimization. That is, how can we get the clients on and off the network as quickly and as efficiently as possible. Much of this is achieved through the implementation of OFDMA, which brings us resource units. The AP works to control which RUs go where and when, and by doing so, can mitigate contention issues that plague prior iterations of WiFi amendments. With ax-capable APs and clients finally starting to be a bit more readily available, expect to see a lot of WiFi engineers tinkering and sharing results to show how well this part of WiFi 6 does-or does not-work.

Now, with the added efficiency, there’s likely to be a corresponding performance increase as well. Where are we most likely to see these gains? Think about the dense deployments-conference halls, training rooms, wide open office floors where end users have three and four wireless-only devices as far as the eye can see. These areas, these very dense deployments, are screaming for something that allows wireless clients to make use of the finite air space more efficiently.

Whether you should make the pitch to move to WiFi 6 is, honestly, a company-specific decision. If you are thinking of it for home, I’d say it would make sense once you have a few devices that are capable of benefitting from it. That’s not likely to be before 2020 for most of us, unless you are an early adopter. For the enterprise, it’s probably not all that different. Most larger companies do have a long refresh cycle, and while 802.11ax is promising and intriguing, it’s not such a game-changer that I’d suggest swapping out hundreds or thousands of access points tomorrow. Why? Well, in addition to the cost and time to replace those APs-which may be perfectly fine 802.11ac models-odds are the majority of your end user devices are not 802.11ax capable now, and probably won’t be for a while.

Just some supporting evidence with that in mind-Cisco first released the 3702i in 2014, with ac wave 1 built in. The 3602i had an available 802.11ac add-on module in 2013. I’ve seen offices only in 2018 or even 2019 have their legacy (3602 or older) hardware replaced with the newer wave 2 capable devices. Part of that was aiming to not be bleeding edge. Part was it dovetailing into a 3 to 5 year refresh cycle. The other component? In 2013 and 2014 when these models hit the market, there were not a lot of 802.1ac capable clients in the environment-probably fewer than 10% for the first couple years.

So what’s the point? Well, you might have someone hot to upgrade, but you need to evaluate your environment, or that of your customer. Are the devices capable of the latest and greatest? If not, will they be soon? Is the existing WiFi infrastructure in need of an upgrade? Those are the important questions. If the WiFi hardware is EOL, then it could make sense to move forward, even if the clients aren’t in place yet. But, if the business lacks the installed client base AND has relatively new WiFi gear? It’s probably wisest to tell leadership that they can delay any upgrades for now. Besides, as of early September of 2019 (when this was written), the 802.11ax amendment’s certification program was still not released-meaning that while radios and chipsets based off of it have been shipping, it’s still theoretically possible for the actual standards to change, even if at this juncture it’s increasingly unlikely.

The takeaways here? There’s no inherent reason to rush to switch to WiFi 6. There are things any engineer should evaluate before recommending any upgrade to their infrastructure, and this is as true for a move to WiFi 6 as it was for any of it’s predecessors, and will be for WiFi 7 and beyond. Is the tech promising and exciting? Sure. But it also has real costs to procure and implement, and those are not inconsequential. Every new WiFi version is worth understanding and evaluating, but the reality is such a major change will require new infrastructure and new client devices, which means costs can skyrocket. It’s not a change to be done every year.

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