What’s next for Wi-Fi?

If you need to upgrade now, upgrade to Wi-Fi 6

Today, for most people who are considering new networking gear, next-generation Wi-Fi means IEEE 802.11ax, with certified units bearing the Wi-Fi 6 logo. Flagship smartphones equipped with Wi-Fi 6 include Apple’s iPhone 11 and Samsung’s Galaxy S10.

Although relatively few notebook computers in stock configurations have Wi-Fi 6, compatible routers have been widely available since 2019. As usual, advertisers make the most optimistic claims possible, and theoretical throughputs can be nearly 10Gbps. But real-world data rates for an individual Wi-Fi 6 user are closer to 1Gbps.       

The latest Wi-Fi equipment also delivers substantial improvements to user experiences – not simply in terms of data rate, but also in the number of connected users and devices, as well as reduced delays. The Wireless Broadband Alliance had claimed that during trials, its member companies had demonstrated “consistent two-millisecond low-latency connection”.

Intel was less bold in its claims, reporting that simulations of nine client devices on a Wi-Fi 6 network predict that latency will average 7.6ms.

Game enthusiasts and high-frequency financial securities traders still prefer wired Ethernet, with delays well under 5ms, and in engineered systems, well under 1 microsecond. But the most demanding PC gamers are not demanding Wi-Fi 6 much, or not yet. Users of consumer electronics will reportedly have a chance to experience Wi-Fi 6 capabilities when the PlayStation 5 arrives on store shelves in November.

Network managers and small offices are accustomed to upgrades in Wi-Fi technologies that take place over a period of years, as users acquire new hardware. Wi-Fi 6 seems likely to require a few years to become truly pervasive. Before that occurs, market development might seem somewhat slow in the early phases of a new standard.

Cisco anticipates that about 27% of wireless LAN endpoints in service will be compatible with Wi-Fi 6 in 2023. Even so, any network manager that expects to serve a number of late-model premium smartphones from a single access point now has reason to plan for upgrading access points and hotspots.

You might want to wait until 2021 for Wi-Fi 6E

Before you jump on this year’s model of the Wi-Fi 6 bandwagon, you might want to look at what’s on the drawing board – namely, Wi-Fi 6E. UK regulators recently decided to allow unlicensed use of about 500MHz of spectrum in what is commonly known as the 6GHz band. That decision nearly doubles the amount of spectrum available to Wi-Fi in the UK.

US regulators went somewhat further, opening an enormous band of frequencies that includes the entire span from 6GHz to 7GHz, with some of the frequencies to be available only with the aid of real-time online mapping and channel-coordination services. The result could nearly triple the amount of spectrum available to US Wi-Fi users.

The Wi-Fi Alliance said it will start certifying devices that are compatible with the 6GHz band using the Wi-Fi 6E logo starting in early 2021, but Asus, for one, has already announced “the world’s first Wi-Fi 6E router”, and promised availability in December 2020.

Wi-Fi 6E promises to solve problems in areas where Wi-Fi use is currently congested. Yet the Covid-19 pandemic seems to call into question the importance of serving many users in crowded places.

For years, network managers have needed to face challenges to serve many users who are closely spaced in transit hubs, sports venues and large indoor spaces. When and if business and social conditions improve, the task of managing peak demands for Wi-Fi in transit hubs during rush hours will become a problem again, as it has been in the past.

Those who wait could face decisions about Wi-Fi 7

Since 2019, the IEEE’s 802.11be task group has been working towards a future Wi-Fi 7 standard that will likely handle 40Gbps of total traffic per router, roughly quadrupling the throughput of Wi-Fi 6. Developers of 802.11be have proposed fairly aggressive schedules and a staggered sequence of improvements that are slated to appear during 2021 until early 2024. By the end of that period, the Wi-Fi Alliance might establish a Wi-Fi 7 certification procedure.

However, manufacturers could implement an early draft of IEEE 802.11be that is slated to receive approval in 2021, and whose major design aspects are already somewhat clear. Preliminary Wi-Fi 7 products might allow practical portable devices to receive and transmit roughly 3 to 4Gbps by doubling the maximum channel bandwidth (from 160MHz to 320MHz), allowing up to 16 antennas per router, and using improved modulation techniques.

Computer makers seem to be puzzling over whether to commit to Wi-Fi 6 now or wait for Wi-Fi 6E to emerge. A year from now, network managers and designers of connected products could be asking themselves whether to commit to Wi-Fi 6E or wait for early implementations of 802.11be. And two to three years from now, the question of whether to wait for a complete Wi-Fi 7 standard could be on people’s minds.

Future versions of Wi-Fi versus future versions of 5G

Wi-Fi and mobile-service developers seem to be on a collision course, with similar motivations and aspirations to deliver two advanced sets of applications – wearable augmented reality (AR) and industrial-scale wireless networking. Both applications need low delays.

In the case of augmented reality, smart glasses need to respond rapidly to changes in head position and events in the environment, lest users experience lag and symptoms that resemble those of motion sickness. In the case of industrial networks, low delays are important because signals in one machine can control other machines with split-second timing.

In industry, wireless technologies might reduce or eliminate complex wiring harnesses that can be difficult to service. Wireless technologies can also simplify the process of adding, moving or changing equipment. However, industrial automation has a strong tendency to rely on wires to enable both high reliability and very low signal delays.

With these requirements in mind, 5G developers and service providers have aimed to serve industrial users in recent years. Elements of 5G called ultra-reliable and low-latency communications (URLLC) and direct device-to-device (D2D) 5G connections could migrate from current emergency-radio developments to industrial developments.

But some factors still favour Wi-Fi for industrial applications. Indoors, Wi-Fi promises to remain the economical choice that takes advantage of economies of scale. Organisations will not need to sign up for additional cellular accounts, and they will always have the option, but never a requirement, to use managed and outsourced Wi-Fi services.

Also, developers of internet-of-things (IoT) applications seem likely to use emerging features of Wi-Fi to shave power requirements, enabling battery-operated devices to run for long periods without maintenance. An aspect of Wi-Fi called target wake time (TWT) enables client devices and routers to coordinate and schedule data transfers, with client devices remaining in low-power modes until an appointed time.

Even smart-glasses applications seem likely to favour Wi-Fi, at least in the near term. Considering that recent smart glasses have not fulfilled people’s fantasies about futuristic lifestyles, users are likely to continue to see solutions that emphasise indoor use for a few hours at a time before developers can reduce size, weight and battery requirements enough for all-day outdoor use.

So far, makers of augmented reality headsets, such as Magic Leap and Microsoft, have opted to mainly sell directly to consumers and businesses, not through cellular-service channels. But perhaps in the late 2020s, AR eyewear will be a smartphone accessory, with smartphone makers supplying the hardware and 5G networks supplying the signals.

For now, HTC’s Vive virtual-reality headset has a wireless option that depends on WiGig, a lesser-known variant of Wi-Fi that relies on 60GHz microwave frequencies. Users seem to be satisfied with the responsiveness of the wireless option for Vive, but WiGig has limited range and limited abilities to penetrate walls.

If developers want to support AR platforms that someone can wear for extended periods, they will need to rely on high-data-rate connections that have at least the scale of coverage users they expect from today’s Wi-Fi networks.