There is a major battle brewing for control of the connections that control the Internet of Things. Today in the early stage of home IoT most devices are being connected using WiFi. But there is going to be a huge push to have connection instead made through 5G cellular.

I saw an article this week where Qualcomm said that they were excited about 5G and that it would be a world-changing technology. The part of 5G that they are most excited about is the possibility of using 5G to connect IoT devises together. Qualcomm’s CEO Stephen Mollenkopf talked about 5G at the recent CES show and talked about a future where 5G is used for live-streaming virtual reality, autonomous cars and connected cities where street lamps are networked together.

Of course, Qualcomm and the cellular vendors are most interested in the potential for making money using 5G technology. Qualcomm wants to make the hundreds of millions of chips they envision in a 5G connected world. And Verizon and AT&T want to sell data connections to all of the 5G connected devices. It’s an interesting vision of the world. Some of that vision makes sense and 5G is the obvious way to connect outdoors for things like street lights.

But it’s not obvious to me at this early stage of IoT that either 5G or WiFi are the obvious winner of the battle for IoT connectivity in the home. There are pros and cons for each technology.

WiFi has an upper hand today because it’s already in almost every home. People are comfortable using WiFi because it doesn’t cost anything extra to connect an IoT device. But WiFi has some natural limitations that might make it a harder choice in the future if our homes get filled with IoT devices. As I’ve discussed in some recent blogs, the way that WiFi shares data can be a big problem when there is a lot of steady and continuous demand for the bandwidth. WiFi is probably a great choice for IoT devices that only occasionally need to make a connection or that need short-burst connections to share information.

But the WiFi standard doesn’t include quality of service and any prioritization of which connections are the most important. WiFi instead always does its best to share bandwidth, regardless of the number of devices that are asking to connect to it. When a WiFi router gets multiple demands it shuts down for a short period and then tries to reinitiate connections again. If too many devices are demanding connection, a WiFi system goes into a mode of continuously stopping and restarting and none of the connections get a satisfactory connection. Even if there is enough bandwidth in the network to handle most of the requests, too many simultaneous requests simply blows the brains out of WiFi. The consequence for this is that having a lot of small and inconsequential connections can ruin the important connections like video streaming or gaming.

But cellular data is also not an automatic answer. Certainly today there is no way to cope with IoT using 4G cellular networks. Each cell site has a limited number of connections. A great example of this is that I often talk to a buddy of mine in DC while he commutes, and he usually loses his cellular signal when crossing the between Maryland and Virginia. This is due to there not being enough cellular connections available in the limited area of the American Legion bridge. 5G will supposedly solve this problem and promises to expand the number of connections from a cell site by a factor of 50 times or so – meaning that there will be a lot more possible connections. But you still have to wonder if that will be sufficient in a world when every IoT device wants a connection. LG just announced that every appliance it sells will now come with an IoT connection, and I imagine this will soon be true of all appliances, toys and almost anything else you buy in the future that has any electronics.

Of a bigger concern to me is that 5G connections are not going to be free. With WiFi, once I’ve bought my home broadband connection I can add devices at will (until I overload my router). But I think Verizon and AT&T are excited about IoT because they want to charge a small monthly fee for every device you connect through them. It may not be a lot – perhaps a dollar per device per month – but the next thing you know every home will be sending then an additional $50 or more per month to keep IoT devices connected. It’s no wonder they are salivating at the possibility. And it’s no wonder that the big cable companies are talking about buying T-Mobile.

I’m also concerned from a security perspective of sending the data from all of my IoT devices to the same core routers at Verizon or AT&T. Since it’s likely that the recent privacy rules for broadband will be overturned or weakened, I am concerned about having one company know so much about me. If I use a WiFi network my feeds will still go out through my data ISP, but if I’m concerned about security I can encrypt my network and make it harder for them to know what I’m doing. That is going to be impossible to do with a cellular connection.

But one thing is for sure and this is going to be a huge battle. And it’s likely to be fought behind the scenes as the cellular companies try to make deals with device manufacturers to use 5G instead of WiFi. WiFi has the early lead today and it’s still going to be a while until there are functional 5G cellular networks. But once those are in place it’s going to be a war worth watching.