The Wi-Fi 6 standard and the coming 5G mobile communications offer high data rates of more than 1 GBit/s. The two standards complement each other rather than being competitors. For example, Cisco regards the future for Wi-Fi 6 to be more within buildings, and for 5G rather in connecting the world outside.
Videos, mobile business applications or IoT devices which send and receive data in real-time – the demand for mobile bandwidth is growing. In Germany, mobile data traffic per inhabitant is predicted to almost quadruple – increasing from 1.2 to 4.5 GByte per month between 2017 and 2022. This is shown by the current Cisco Mobile Visual Networking Index. Mobile traffic per connection (including machine-to-machine communication) will also increase from 0.7 to 1.5 GByte per month. This means mobile communications and Wi-Fi networks will reach their limits increasingly often.
Wi-Fi 6 and 5G complement each other
The new standards – Wi-Fi 6 (802.11ax) for Wi-Fi and 5G for mobile communications – should help resolve this problem. Both are based on fundamentally similar technology and have the core task of supplying companies and private citizens with data rates of more than 1 GBit/s. This begs the question: do we really need both technologies? Isn’t it about time we agreed on a single wireless standard? The answers are YES and NO.
The network equipment provider Cisco regards the two standards as complimentary technologies which mutually reinforce each other. “Wi-Fi 6 is the new standard for indoors and 5G for outdoors. New end devices will offer a rapid switch between 5G and Wi-Fi in order to make the best use of available access technology”, said Falko Binder, Head of Enterprise Networking Architecture at Cisco Deutschland, talking to Golem.de. For cost reasons, 5G won’t be replacing Wi-Fi any time soon.
To support both technologies, the US company will extend its 5G portfolio, in addition to its large Wi-Fi 6 product range (routers, switches and cloud services such as Meraki). Over the next three years, Cisco is planning to invest five billion US dollars for this purpose.
Wi-Fi 6 and 5G – commonalities and differences
The most striking thing about Wi-Fi 6 is the new naming convention. Instead of complex IEEE abbreviations such as 802.11n (now Wi-Fi 4), 802.11ac (Wi-Fi 5) or 802.11ax (Wi-Fi 6), current and future Wi-Fi standards will now have simple designations. Compared to Wi-Fi 5, Wi-Fi 6 achieves speeds which are up to 1.5 times faster: the new standard theoretically enables a maximum speed of up to 4.8 Gbit/s per client. For Wi-Fi 5 this maximum is 3.12 Gbit/s. 5G should achieve similar data rates. In reality, the bandwidth will probably be significantly lower, since internal and external walls will damp the radio waves and the speed will decrease with increasing distance from the router or the mobile communications mast.
Like 5G, Wi-Fi 6 is All-IP and therefore suitable for all data traffic. What’s more, both standards rely on Orthogonal Frequency Division Multiplexing (OFDM). Thanks to finer signal division, OFDM reduces transmission delays when many participants are using the network at the same time. When many end devices and IoT devices are connected via Wi-Fi, Wi-Fi 6 provides a significantly more reliable network connection as it can process large data flows simultaneously.
One big difference is in the provisioning. Mobile communications (3G/4G/5G) use licensed frequency bands. Mobile communications operators pay money in an auction for the exclusive use of these bands. After all, they must invest in a network of base stations in order to cover a larger area. To finance these costs, operators demand (subscription) fees from their customers, including for the SIM card. Here interferences are not a big problem. In contrast, Wi-Fi 6 works on unlicensed frequency bands. So interferences always play a role. However, these can be reduced by using smaller cells or with protocols for combating interferences.
Another difference: for Wi-Fi 6, there are already a range of access points, smartphones and business applications currently on the market, from numerous providers. In contrast, 5G is still in its infancy in this country. It is to be anticipated that the first 5G services in urban areas will be only available from 2021.
5G outside, Wi-Fi 6 inside
Universal 5G coverage is not on the horizon yet and would be very expensive. To achieve this, an antenna would have to be erected at least every 1000 metres, as 5G has a maximum range of around 500 metres. And this would not mean that 5G would be available everywhere inside buildings. The new mobile communications standard is primarily suited to networking mobile devices and processes outdoors: for example, in autonomous vehicles or smart cities, where traffic is controlled using real-time data. Here Cisco (see above) agrees with the majority of experts.
In this context, Wi-Fi 6 is most useful in indoor applications. Compared with previous Wi-Fi standards, it offers higher data rates, lower latency, more stable connections plus a higher device density in the network. It will be of most benefit to, for example, users in airports, stadia, trade fairs, company premises and production halls.
The most important thing for efficient communication and mobile networking in the future will be for 5G and Wi-Fi 6 to work together, and that the transition between the two channels functions smoothly. New end devices will enable rapid transition between 5G and Wi-Fi 6, to find the best technology for the current requirements. Users won’t care if they are online via 5G or Wi-Fi 6 – the main thing is that the connection is fast enough.