Private 5G: The 4 things that determine if you need it

By this time, you’ve probably read so many stories about enterprises adopting private 5G networks that you feel like a student who finds out they’re not one of the cool kids. Can you ever hold your head up in a tech conference and admit you’re not running private 5G yet?

Take heart!  Maybe you’re not supposed to be. The best wireless network technology for an enterprise depends on four things: devices, spread, privacy, and mission.

5G is a cellular network technology used almost exclusively by telcos, but you can buy equipment to build your own 5G network, and even get hosted 5G from cloud providers like Amazon. You can use open spectrum so you don’t need to bid at an auction for a license. There’s a lot of excitement about private 5G, but in that excitement it’s easy to forget that you could have adopted private 4G/LTE long ago, and that Wi-Fi is still the most popular wireless technology of all.  You’ve got to look at the four factors just mentioned to decide whether you want to read about private 5G or adopt it.

Mobile devices

Let’s start with devices, and here we find the simplest first question to ask: Do I plan to use smartphones, mobile tablets, or mobile IoT devices with my wireless, and keep a session alive while moving?  If the answer to that question is, “No,” then you’re almost surely not going to get much from private 5G.  All private wireless technologies will build networks from small cells, and the big benefit of 5G or 4G/LTE is that they can keep a call connected as you roam between these cells, just as they do in the public network. If the devices you plan to use aren’t moving around a lot, then that capability doesn’t matter.

So if you do plan on devices that move around, you need private 5G, right?  Not so fast.  First of all, 4G/LTE technology is also available in private form, and anyone considering private 5G should look at the “older” wireless technology closely. 5G will support faster downloads, but whether that matters depends on whether you’re actually downloading something large.  For workers who use laptops, download files, and move around in their jobs, 5G might make a difference.  Otherwise, if you’re sure download speed isn’t an issue, go with whatever is cheaper.

Roaming

Note, though, that I said 5G might make a difference. This brings us to the second of our considerations, spread.  Expecting moving devices is important, but so is how spread out their movement is likely to be. Consider the extremes; do you have a building you’re trying to connect wirelessly or do you want connectivity across a country or continent.

If all you want to do is support mobile sessions within a building, then private 5G or even 4G/LTE is overkill.  There are any number of Wi-Fi calling applications that will work for voice or video calls, and Wi-Fi roaming is an established strategy, standardized in WiFi 802.11k, 802.11r, and 802.11v, though you need to test out your gear to make sure it works for you. Wi-Fi 6 supports OpenRoaming, which lets you roam between W-iFi 6 networks and 5G networks.

That’s important at the other end of our spread extremes. No one is likely to build a national or multi-national private Wi-Fi network except perhaps a government body. The more your desired wireless coverage area is spread out, the more likely it is that you’ll need to rely on some form of public network for some or most of it.  That doesn’t mean you need to abandon Wi-Fi in your facilities; just get Wi-Fi 6 and OpenRoaming.

You might think that public 5G and WiFi 6 OpenRoaming solve all your private wireless problems, but not so. One area where you may still find private 5G useful is in between those extremes. Imagine you have a very large college campus or maybe a big transportation yard or even a highly automated large farm. Wi-Fi 6 has a very short range compared to private 5G, and so for large areas it may be difficult or impossible to provide uniform Wi-Fi coverage. You do have to be careful with private 5G if your facility is in a population center, because shared spectrum can create collisions and reliability issues, and 5G’s greater range increases that risk, but it’s vertical industries like these that present the most realistic opportunity for private 5G.

Protect sensitive communications

Why not just stay with public 5G, then? That gets to our next consideration, which is privacy.  Some enterprises have to support communications that are totally protected, that don’t want to be on an open network at all.  Private 5G may seem like a good option for this, but don’t forget the scope issue. If you need to protect voice calls, it may be smarter to use an encrypted calling application on public wireless. Data connections can typically be encrypted at the application level, so that should provide sufficient protection for downloads, VPN access, etc.

Privacy isn’t all about security, of course. It also assures you aren’t competing with others for resources.  Public 5G could still result in blocked calls and capacity limits.  This is most likely to happen in population centers, though, which are the very places where private 5G is likely to face spectrum competition. One option is network slicing, a 5G service that lets an enterprise carve a kind-of-a-VPN out of 5G resources. Slicing isn’t widely available at this point, but it is expanding and when it’s available, may cover your areas of interest.

Is 5G the best way for you to support new tasks?

Speaking of interest, it’s time to move to the last of our four considerations—mission.  It’s never a good idea to lose sight of what you’re actually trying to accomplish, but in networking it’s a very bad idea. The best place to start is to ask a simple question: “Am I trying to do anything different than I’m doing now?” If the answer is, “No,” then whatever your current wireless technology may be is likely working, and you should have a very solid reason for making any sort of change.

Even if you are going to be doing something different in the future, you still need to ask yourself why you believe your current technology won’t support that new mission. Any decision to change technologies radically—and make no mistake, private 5G is a radical change—has to start by justifying why any change is necessary.  Be sure you can do that before you yield to eager vendors who want to sell you private 5G or you may regret your decision.