There’s a lot of chatter at the moment about 5G and whether or not it will replace WiFi. Obviously it’s in our interest to be asking, once you get access to wireless connectivity that is faster, more robust, and has greater capacity than Wi-Fi, why would you need that and Wi-Fi? Why wouldn’t 5G replace Wi-Fi? Over the last couple of years people have been asking this question again and again, because theoretically it is possible.
EDN asked a Wi-Fi industry specialist about 5G replacing Wi-Fi, and at first they didn’t even understand the question. The reason for the confusion became clear after a bit of discussion. Simply, it makes no sense. For 5G to replace Wi-Fi, the wireless carriers would have to want to make it happen, and obviously they have no reason to want it to happen.
Wi-Fi is most widely used for the residential market, distributing broadband bandwidth among a growing number of devices. Of course there are public hotspots and other things that rely on Wi-Fi too but residential service is where Wi-Fi is used most.
Logically, there are many reasons why homes will continue to rely on Wi-Fi.
We already use thousands of products where Wi-Fi is already built in, and there are thousands more coming. All the tech that we currently use, like tablets for example, have nothing but Wi-Fi and so need to be supported for a long time yet. Maybe some people will decide to get 5G broadband, but the signal is more likely going to go to a gateway and get distributed via Wi-Fi from there.
Even if, for whatever reasons, carriers decided to replace Wi-Fi, it would not be an immediate thing. There are 90 million to 100 million homes that would require femtocells. So even if consumers demanded it, or operators wanted to do it, it would take years to deploy that many devices. Also, consumers wouldn’t replace all of their tech straight away, and would continue using legacy devices, so even if things were to turn towards 5G, it would still have to co-exist with Wi-Fi for many years after that.
There is also no compelling technological reason to replace Wi-Fi anyway. Technology is always improving and subsequently getting faster, more robust, and capable of supporting an increasing number of Wi-Fi devices simultaneously. Repeaters are becoming more common and mesh networking is also on the way in the forthcoming IEEE 802.11ax generation of Wi-Fi technology, which is being branded as Max Wi-Fi.
5G signals are a shared resource. If you have a hundred homes served by a single base station, that 1 Gbps gets distributed, averaging out to 10 Mbps to each home. But if people want gigabit service, they want a full gigabit, and that service is still best provided by cable or DSL which will get distributed throughout the home by Wi-Fi.
Those conditions likewise apply in the enterprise market, which is unlikely to give up Wi-Fi any time soon. Urban access, in areas served by public hotspots can do this with LTE now (a 4G telecommunication standard).
In simple terms, if Wi-Fi was going to be replaced in urban environments, then it would be happening already. If it’s not happening for LTE then it’s unlikely it’ll happen for 5G.
The only place where 5G might possibly end up getting used instead of Wi-Fi would be where wireline connectivity is lacking or inadequate in rural areas, but even this is purely speculative. In most experts minds, 5G will never replace Wi-Fi.
There are 3 challenges that Wi-Fi equipment developers are in the process of overcoming: more devices in more places, most requiring greater speed, with some requiring significantly lower latency.
For example, the Amazon or Google home devices that are becoming more prevalent need to be answering consumers questions in well under a second.
According to the experts, 802.11ax will address all three issues. It will be faster, and will support mesh networking. It will also support more channels to handle more devices concurrently. Max Wi-Fi will adopt the OFDMA (orthogonal frequency division multiple access) modulation scheme to support traffic scheduling, which will be kind of handy in residential environments but immensely valuable in situations where thousands of users are packed together, arenas and stadiums, for example. There are also provisions for spatial reuse.
Work is always being done to improve Wi-Fi to complement other connectivity options that include 5G. There are several local and personal area network (LAN, PAN) communications options, and they will have to be made to work with each other.
Wi-Fi operates in the 2.4 GHz and 5 GHz channels, but Bluetooth 5, Zigbee, and Thread – three low-power technologies – are all operating in the same 2.4 GHz band. Wi-Fi is more powerful and can overwhelm the others, but they’re going to have to co-exist. (By the way, Max Wi-Fi has a low-power profile as well, and might end up competing with the other three in some applications).
We are seeing gateways specified with all four radios: Wi-Fi, Zigbee, Thread, and Bluetooth. It’s up to infrastructure companies to sort out the coexistence issues.
So 5G versus Wi-Fi? It doesn’t have to be a competition; they will very much be co-exising with each other.
