@Commscope

Backwards Compatibility of Wi-Fi

f there is one thing that Wi-Fi professionals like to complain about (there are many things we like to complain about, but this time we will focus on just one thing), it’s the backwards compatibility that exists within the 802.11 standard. Until the 6 GHz spectrum was released with Wi-Fi 6E, older protocols and standards were still officially supported in the latest releases. Sure, 802.11b is old and antiquated and yes, WEP was cracked in 2001, but even today they all can still be enabled and configured in the legacy bands.

You shouldn’t ever do that (WEP and/or 11b), but there are times when our hands are forced. Many times, the client devices we are asked to support in our networks force us to do things on our networks we know we shouldn’t do, and don’t want to do, but we aren’t left with much of a choice. Our only lifeboat in this backwards compatibility is that it didn’t transfer to the 6 GHz spectrum, which is another reason that Wi-Fi professionals love 6 GHz.

That doesn’t help Internet of Things (IoT) devices at all. This is where the latest standards collide with what the users of our networks (the true customers) want to have function in their lives. To make it sound less like a train wreck and to soften it up, many times we use the term “converge” to help cushion the ask, but to be real, it’s a collision

As network professionals, we are asked to provide stable connectivity to devices that run the gamut from high end computing devices like computers and even servers, all the way down to the plethora of IoT devices coming to market each and every day. Managing this convergence of the latest Wi-Fi standard of 802.11be (Wi-Fi 7) with the myriad of devices intended to make our spaces “smart” is a monumental effort for certain, but it’s one we can, and must, orchestrate to ensure that the customers (end users and organizations alike) achieve the connectivity that they need and desire.

Managing the Convergence

Even as we are drawn to the high end of the specification sheets of the latest generation of Wi-Fi Access Points (AP) that are out today with Wi-Fi 6E, I can promise you that the specifications that are coming with the Enterprise grade Wi-Fi 7 APs are going to be even more. With a top end speed of at least 30 Gbps (compared to the 9.6 Gbps we see today) it’s easy to understand the draw. With a name like Extra Hight Throughput (EHT) you really can expect a lot from those top end numbers.

Lost in all this excitement of the specifications of Wi-Fi 7 is the explosion of the Internet of Things. Things like appliances, light fixtures, power outlets, the list is endless, and they are also joining our networks today along with those high-powered computers.

How network engineers manage this integration of high-end devices needing multiple Gigabits per second with devices like appliances and light fixtures, all needing wireless connectivity, will be a defining factor of where technology, and society, will find itself in the next 5 to 10 years.

Multiple bands, mulitple protocols

Complicating this convergence of Wi-Fi 7 with the Internet of Things is the fact that not all IoT communicate using the same protocol as Wi-Fi devices. While devices like computers, tables, and phones primarily use 802.11 for their connectivity, IoT devices might communicate in the same band (2.4 GHz) but use different protocols like 802.15.4[1] (Zigbee) or Bluetooth Low Energy[2] (BLE). To complicate matters, IoT devices might also use 802.11 to connect in 2.4 GHz, likely meaning they are taking advantage of the backwards compatibility of Wi-Fi, and they are using 802.11n (Wi-Fi 4) on our shiny new Wi-Fi 6E APs. This will also be the case when Wi-Fi 7 APs start to hit the market in the next 12 to 18 months, possibly even sooner.

If that isn’t enough, some IoT devices use other IoT protocols that utilize bands not traditionally available for 802.11, protocols like Z-Wave[3] that utilizes 900 MHz and its own communication protocols. For a seasoned veteran of the radio world the addition of Z-Wave and even Wi-Fi HaLow[4] represents a slight complication of what is needed. For everyone else, this simply represents more acronyms and initialisms that can be added to the letter and “word salad”[5] that is the wireless technology of today. People don’t know what it is or how it operates, they just know that they want it to work.

“Make it to work”

Decades ago, I was having a conversation with a sales professional who had the misfortune of asking me a technical question. Being a brash young technologist, I proceeded to go into great detail of how everything worked; the spectrum, the protocols, the advantages, the disadvantages, and other possible solutions to the question posed. This kind person patiently waited until I was done explaining everything and then looked at me and said, “If I ask you what time it is, please don’t tell me how to a build a watch” and then turned and walked away.

Years later, while talking to an electrician, I used this lesson I learned when discussing a project I was in charge of. The electrician looked at me and said, “you just want me to ‘make it to work’.” Confused by the grammar, I asked them to explain. They said their previous boss, whose first language wasn’t English, would use that term to convey the message that he didn’t care how they accomplished the task, that he just wanted to accomplish the task at hand to the satisfaction of the customer.

Both of these experiences from my past sum up where we as wireless professionals find ourselves today.

Our customers (both the organizations we support and their end users) don’t understand all the nuances of the different wireless spectrums and protocols that are in use today. From Wireless Body Area Networks (WBAN, wireless networks that don’t extend past a person’s body) to Personal Area Networks (PANs, less than 1 meter) to Wireless Local Area Networks (WLANs) to Wireless Metro Area Networks (WMAN & WiMAX) to even wireless WANs (multiple WLAN’s connected wirelessly over a large regions) the options, specifications, protocols, spectrums, the works, are confusing to even the most knowledgeable professional.

Now, think about everything in that previous paragraph and imagine you aren’t in wireless or even in IT. You have suddenly become that sales professional who just wanted a simple answer.

Making Complex Solutions Appear Simple

In the world of sport, most people agree that the definition of a professional athlete is someone who performs an athletic feat and makes it appear simple and easy. It makes you think “Hey, even I could do that!”, all while realizing that no, we can’t do that windmill kick over our head and past 5 defenders to score a goal. Even typing that I pulled a muscle and need to go take some medicine and relax a bit.

This convergence of 802.11be (Wi-Fi 7 Extremely High Throughput) with the explosion of IoT devices running any number of protocols across multiple spectrums requires the Wi-Fi professional of today to become a wireless professional of tomorrow. We already explain there is a difference between the 5 GHz spectrum of Wi-Fi 5 & 6 and the cellular technology of 5G, so this is simply another task that needs to be taken on in making the equivalent of that windmill kick but in the wireless world.

The bigger question is how do we make this complex and difficult task look easy to our customers and end users?

Have a Plan

This has been discussed before but understanding the differences between device requirements is key to creating a plan to deal with this convergence of technology and requirements. Benjamin Franklin, an American statesman and author, once famously said “If you fail to plan, you are planning to fail!”[1] I would add that having an incomplete plan, while better than no plan, isn’t that much better than no plan at all.

Part of this plan needs to account for actual needs and requirements, not just the wants of the end users. While we would all love to get 1 Gbps speed tests on all of our devices across all of the bands, that just isn’t going to happen. 1 Gbps, while for some applications might be a requirement, for most, it’s going to fall into the “want” category. Our plans for the future are going to need to separate the wants from the needs and make hard decisions for the greater good of the entire network.

Design fundamentals to support a converged network

Many times, I have heard people declare that the 2.4 GHz band is “dead”[2] only to realize that it’s not dead, it’s just not the right spectrum for dealing with the requirements of the network and the end users. Once we have a plan in place that incorporates the needs of the devices and the end users balanced against the wants, we can then make some design decisions to accomplish our goals. As much as we bemoan devices that only have a 2.4 GHz radio, sometimes that is all that is needed.

Client assignment

Designers need to think of the bands much like the encryption used today. To enable a converged network, only those clients that can fully utilize the benefits that comez with the 6 GHz spectrum should use that spectrum. Requirements like Virtual Reality (VR) and Augmented Reality (AR) or any other specially curated use cases should be using that spectrum today. The truth is that 98% of users today, not counting VR/AR, are functioning well using the 5 GHz spectrum. While everyone likes to go fast, it isn’t something that is needed.

Architects and engineers need to think of band utilization in a new concept, something like this:

Figure 2: Wi-Fi Spectrum Allocation

While not a hard and fast rule, keeping devices in a band that will work for them is the best starting point to allow devices to have the best chance at achieving their desired performance levels across all the bands. Wi-Fi 7 is the second generation of the 6 GHz expansion, so we expect to see all of the lessons learned from Wi-Fi 6E applied to Wi-Fi 7 to allow the devices that really need that spectrum and performance to able to operate efficiently and at the level they need to. Our job is to make sure that the sensor that can afford a 500ms delay stays in the band where 500ms of delay isn’t uncommon – the 2.4 GHz band. Leave 5 GHz for the phones, tables, and laptops that don’t need massive speeds and latency critical applications and we now have a plan to run and manage our converged network.

Wi-Fi 7 converged with IoT

For every computer that comes with a 3×3:3 Wi-Fi 7 radio that wants to move data at 5 Gbps, there will be five devices that don’t need anything near that. These devices will have 1×1:1 radio that move data measured in the bits per second, and even then, only a couple of times an hour. They might even only support the 2.4 GHz band, but even if they do support 5 GHz, why even let them in that “lane”?

Converged networks from CommScope RUCKUS, “making IT to work” for you.

Jim Palmer

Senior Product Solutions Architect

RUCKUS Networks


[1] https://www.mouser.com/pdfdocs/digi-wp_zigbee.pdf

[2] RF Wireless World, https://tinyurl.com/4n7symn3

[3] https://www.z-wave.com/learn

[4] https://www.wi-fi.org/discover-wi-fi/wi-fi-certified-halow

[5] https://www.merriam-webster.com/words-at-play/word-salad

[6] https://www.goodreads.com/quotes/460142-if-you-fail-to-plan-you-are-planning-to-fail

[7] https://www.zdnet.com/home-and-office/networking/why-2-4-ghz-is-a-dead-end-for-wi-fi/