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When should I upgrade my business to WiFi 6?

6 min read
wifi6-chipset

There are several factors to consider when looking to upgrade your business to WiFi 6. It may offer real performance boosts for some, but poor value for many others. In this article I will try to help you decide which of these camps you fall into. 

First let’s dig a little into what WiFi 6 is, and why you might want it.

WiFi 6 – What’s in a name?

I’ll cut to the chase, the new name is a marketing move. Non-techie types will be relieved to mask those complicated sounding IEEE standards like 802.11ax (the standard behind WiFi 6), with something that sounds a bit more cuddly.

This type of thing is great for building consumer confidence. Manufacturers will therefore be jolly pleased, as they can more clearly signal the new king to consumers…“WiFi 5 is dead, long live WiFi 6!” 

The IEEE naming conventions aren’t going away – WiFi 6 is just an alias for 802.11ax.

What does WiFi 6 do differently?

Transmission Efficiency

The headline maker of 802.11ax is OFDMA. A WiFi 6 AP now has the ability to break a radio channel into sub-frequencies, and allocate those parts to different clients. This consumes less airtime per client transaction, servicing more clients, more efficiently than in previous WiFi generations. 

It is claimed that the efficiency gains clawed back using this method amount to 4x better throughput per-client in a greenfield WiFi 6 deployment. This is amazing, and therefore we should be a little bit wary until we see real-world data. 

OFDMA is nevertheless very important, especially where there are a large numbers of client devices. Current generation technology really struggles in high-density deployments like stadiums, lecture theatres, airports etc. These environments can become so congested by clients just trying to get a slot to speak; that there is little airtime remaining for the actual transmission of data.

Check out my video below introducing the technology used in OFDMA.

OFDMA – How it makes WiFi ‘Great Again’.

Increased Battery Life

WiFi 6 claims to bring with it battery power savings aimed at the mobile and IoT markets. Devices can make use of the carefully abbreviated “TWT” or Target Wait Time feature, which acts as a sleep scheduler for the device. TWT-enabled APs schedule a check-in time with the client, keeping it associated unless it misses a check-in. The device therefore no longer must be in continual communication with an access point, saving power. 

An additional benefit is that the amount of clients on the network could drop significantly, as many will be ‘asleep’. This could significantly reduce extraneous management frames on the channel.

A word of caution; it still remains to be seen how this will implemented by vendors. From a troubleshooting perspective I can easily foresee sleeping devices resembling a device that has dropped off the network. A network administration headache that would not be welcome while investigating transient connectivity issues.

Co-channel Interference Reduction

In extremely dense deployments, we may find that even in the 5Ghz frequency we cannot avoid channels interfering with one another due to them being adjacent.

BSS colouring has been introduced in WiFi 6 to help alleviate this issue. It allows us to assign a ‘colour’ – an additional numerical value to a channel. This value helps APs differentiate between similar channels.

Without BSS colouring, two APs on channel 48 would get busy signals from each other when in use, causing service degradation as clients wait longer for their opportunity to transmit.

What equipment do I need?

The WiFi Alliance has not yet finalised it’s certification program to ensure interoperability between WiFi 6 devices. So just be aware before rushing ahead to buy the shiny new thing, that manufacturers are currently building their kit based on a draft proposal. This is perfectly normal, but it is still a work in progress. At the moment the schedule for full ratification is Q3 2019. So very soon!

WiFi 6 APs are backwards compatible with non-WiFi 6 devices, but your WiFi 6 user experience will likely suffer unless you replace your entire wireless estate. This is because the upgraded AP will have to treat older devices as its special little guy. The old wireless device has no knowledge of OFDMA for example, so will hog the entire channel width for itself.

It will make a significant dent in the IT budget, but I’d suggest leaving no stone unturned. Replace everything that doesn’t meet the new standard. The performance of your network will be degraded by supporting older, non-compliant hardware, leaving you with a wireless network not much better than before you spent a penny.

What do we want? WiFi 6!
When do we want it? When it makes sense!

WiFi is being utilised more in business, and WiFi 6 will eventually become ubiquitous as it provides some great features. However, unless the spare cash is burning a hole in my pocket, and the current 802.11n/ac deployment is making users throw their laptops out of the window – then I would hold off for at least 12 months. 

Waiting for end-user devices that can utilise WiFi 6 to become a decent percentage of your deployed hardware makes sense for most, with the added benefit of allowing time for any bugs in the first wave of hardware to be worked out. It should also become slightly more affordable as the wave of early adopter recedes. 

There are exceptions of course. There will be home use, SOHO, and very small businesses cases where it is likely that upgrading to modern hardware is relatively inexpensive and painless. These people may as well invest in WiFi 6 and reap the rewards sooner. Similarly for public sector operations (at least in the UK) – where if your school/university/hospital, etc. has unspent cash left at the end of the year then you get a reduced budget the following year; WiFi 6 might be a good way to fritter away some of that pesky taxpayer money.

TL;DR

With WiFi 6 we aren’t witnessing a seminal moment in communications or a great technological advance. What we have is a combination of incremental technical improvements to the underlying mechanisms of wireless communication. As a friend and former colleague once said to me regarding Microsoft Sharepoint; “It’ll revolutionise the way we work.” – it didn’t, and for most businesses nor will WiFi 6. 

This isn’t because WiFi 6 doesn’t bring anything to the party, it definitely does. However, legacy hardware in our mixed technology environments will eat away at the efficiencies by hogging airtime that WiFi 6 clients could be using more efficiently – reducing the impact of its deployment.

I still see 802.11b clients (released in 1999) on my network, and can easily conceive that most networks of any notable size will have 802.11ac clients for at least another 10 years. 

I hope this article has helped make your decision of when to invest in WiFi 6 a little easier. If you’ve enjoyed reading this article, let me know in the comments or give it a ‘like’, so I can provide the content people want to hear about. Thanks!