802.11ax

IEEE 802.11ax (aka WiFi Alliance’s WiFi 6)

I was recently asked what I “thought” of 802.11ax. <gulp!>

Honestly, nothing. I had heard of it but hadn’t seriously looked into it in any depth. Not having a technical background, I was a bit taken aback at being asked this question and, so, waffled for a while before changing the subject. (I think I got away with it! LOL)

However, not wanting to be caught on the hop, like that, again, I thought I’d better look it up and try to learn a bit more about it.

I was so fascinated, by what I learned, that I decided I would share a few of those things in blog format.

Taking a step backwards, I want to explain a couple of basics first…

To start with, 802.11 is a wireless “standard”. It was defined by the IEEE – which is the informal government body of wireless technology. The IEEE, basically, makes the rules. The 802.11 standard denotes which frequencies should be used, what media access control (MAC) and physical layer (PHY) protocols should be used to enable wireless devices to communicate. The current standard is 802.11-2016. Note, there is only ever one current standard at any one time.

The WiFi Alliance is a different organization. It is the association of “big hitter” manufacturers of chipsets and devices and is the leading validation body in the wireless world. It is composed of representatives from companies such as Acer, Aerohive, AMD, Apple, AT&T, Broadcom, Cisco, Comcast, Dell, Intel, LG, Microsoft, Nokia, Qualcomm, Samsung, Sony, Texas Instruments, etc. – which agrees, as a whole organization, to adhere to sections of the IEEE’s standard (802.11) and the subsequent amendments to that standard (802.11a, 802.11b, 802.11g, 802.11n, 802.11ac, 802.11ax, etc.) to ensure interoperability.

So, back to what I learned…

In layman’s terms, the IEEE defined the basics that should be used by all wireless devices, so they can talk to each other. The reason that this was so eagerly, and voluntarily, adopted by the WiFi Alliance was because having a single standard that everyone observed, enabled their devices to talk to other manufacturers’ products, and vice versa.

As technology has advanced and new ideas are developed, obviously, the IEEE has had to tweak its rules to match… and what we know as “amendments” were born: 802.11a, 802.11b, 802.11g, 802.11n, etc. (You can tell which amendment is being observed, by looking at the little letters that come after 802.11.)

The previous iteration to the newest amendment (802.11ax) was 802.11ac.

802.11ac moved everything to the 5GHz band and improved on 802.11n (the previous iteration) dramatically. However, as always, client needs, capabilities, and users need more. Now, we have 802.11x. Previous iterations focused on speed. 802.11ax looks to be heavily focused on efficiency.

Although I am not going to go into any form of technical depth, here are a few cool things I have learned during my Internet search studies:

Dual Band

As I previously mentioned 802.11ac focused only on the 5GHz band, whereas 802.11ax uses both the 5GHz and, now, the 2.4GHz band as well.

This enables 802.11ax benefits to be available in the 2.4 GHz range as well. However, when I excitedly told my technical wireless team about my discovery, they mumbled, “We’ll see,” under their respective breaths, implying that this may not be such a huge benefit after all.

Orthogonal Frequency Division Multiple Access (OFDMA) and Target Wake Time (TWT)

Neither of these were available with 802.11ac.

OFDMA allows an AP channel to be divided into smaller units to allow communication with multiple clients at once – kind of like a Twizzler candy, or a cheese string: you can pull the little strands off the main rope to make “more”. That is what OFDMA does to an AP channel – so that it can have multiple conversations (down each of the separated Twizzler strands) at once.

These abilities apparently, work really well with Internet of Things (IoT) devices – things like your Internet-enabled fridge, or a garden watering system, or a thermostat – things that only have to connect and send information once every so often.

Coupled with OFDMA, TWT enables the AP to schedule the time of day when each of these devices is going to “wake up” and send in its report. The AP selects low-usage times – maybe in the middle of the night – to give a boost to efficiency during high-usage times.

It attempts to alleviate problems such as, for example, the situation where you don’t really want to be trying to get information for a vital work report, only to be slowed down by someone’s garden system telling the cloud that the dahlias need to be watered!

OFDMA makes sure that the AP has capacity to ensure that the newly-woken-up device can send its report before going back to the proverbial land of nod. 😊

New Rules

Previously, an 802.11ac client had to wait, until it, alone, could speak. An analogy could be like taking the bus. The 802.11ac protocols were like making you wait until a seat was available, before you could hop on.

You guessed it… 802.11ax improves on this.

Going back to the bus analogy, 802.11ax allows you to take the bus if a seat is available – just the same as 802.11ac – but it also allows you to hop on the bus, even if there is “standing room only”.

These improvements, I think you will agree, create the potential for much more efficiency and bring the possibility that 802.11ax might be able to offer some significant advantages over 802.11ac.