Last time, we dived into the topic of non-public networks, focusing on mobility aspects and the new capabilities brought by advanced mobile technology (e.g. 5G SA) that will drive a host of new use cases and deployments. Now, let’s look at what makes this kind of private network different from others with which you might be familiar.
There are, of course, different kinds of private networks that have been adopted over the years. What the mobile ecosystem calls an “NPN” is a specific type of network that is based on mobile technology. As such, they will follow an evolution path that is driven by standards organisations.
In this tech tip, we’ll look at a few other common types, so that we can further establish the differences and make clear what is meant by an NPN – and better understand the value of the innovations they offer.
The familiar LAN
In the enterprise domain, private networks are nothing new. Most businesses have their own private networks in the form of a LAN – local area network. These provide connectivity, typically by Wi-Fi, but Ethernet remains common, in a given location, usually an office building. They may be operated directly by the enterprise or provided by the building or facilities manager – in shared workspaces, for example.
They are used to enable local devices to access common storage, servers and the like – although, with many of these applications shifting the cloud, they may just serve the purpose of ensuring access to a router that provides a gateway to the internet or cloud-based services.
Most LANs are closed. That is, only authorised devices and users can access them, based on policies, passwords and other factors that can be used for authentication. That is why many offices have one LAN for their employees, but another that can be used for guests – who may need internet access will on the premises.
A bigger LAN – the WAN
And then there are WANs, which means wide area network. These can take many forms, but one common usage is to describe networks that are built for businesses that have multiple sites. Architects and IT teams basically extend their LAN to different locations, enabling users at each site to access the same resources.
However, the term WAN can also be applied to other kinds of networks that are not restricted to employees of any single business. One obvious example is a mobile network. Technically, these are called Public Land Mobile Networks (PLMNs), which is a term originally coined to distinguish new (back in the late 1980s) mobile networks from the fixed alternatives – Public Switched Telephone Networks, or the PSTN, a topic to which we shall return in a moment.
All mobile networks to which users can subscribe are PLMNs – but the key benefit that they offer is roaming. As you know, roaming allows a subscriber of one mobile network operator to connect to mobile networks in another country (or, even, another network in the same country). They are private in the sense that only authorised users can access them, but they are generally said to be public.
Exploring different WANs
The PSTN is also a private network, in that only subscribers can access the services they deliver. But, it is also open, in that, once you have a subscription of one form or another, you can reach any other subscriber, anywhere in the world.
In most countries, there are multiple providers of both PLMNs and PSTNs, although the latter term is slipping from use, and there are other service providers that deliver their offers over the networks of those that actually own and build this essential infrastructure. However, for our discussion, we want to retain the focus on private networks, so that’s enough about PLMNs and PSTNs for now.
Another kind of WAN is a railway network. These are distinct and separate from any public networks and closed to users. They exist because railways require intensive internal communication for their safe operation – not only communication between employees, but also for signalling control and direction.
As such, they are closed, private networks and provide connectivity for their authorised users, equipment and assets, like security systems, for example. Even station clocks are considered as assets, because these need to be tightly synchronised for accurate delivery of passenger information!
You may have noticed that many public spaces now offer Wi-Fi connectivity. A good many cities or stadiums have deployed Wi-Fi infrastructure, for example, to provide public connectivity. These are also a form of WAN, although one that only offers data services. Connectivity may be open or may be restructured to valid accounts.
The list goes on – the point is that networks are everywhere and frequently overlap. Most are, by definition, private, in the sense that access is restricted to those with an account, or the right credentials. Anyone who has filled in a form to obtain Wi-Fi access has joined a private network – and few of us can imagine life without them today!
Finally, in addition to rail networks, there are also networks that are closed because they serve specific use cases – most utility companies have their equivalent of rail networks. These are closed to protect the integrity of the users and devices to which they connect – you can’t have just anyone using a network dedicated to a power station, for example.
Private networks – what makes an NPN different?
So, private networks are everywhere and serve multiple purposes, whether of the local or wide area kind. We use them, all the time, and are (mostly) familiar with the Wi-Fi technology on which some many have been built.
But a LAN or a WAN in the sense of a truly closed network may be built from other technologies – they may use special protocols and interfaces to increase security, capacity or to support specific kinds of network traffic. There’s a world of difference between such a network and one that’s provided for general access. And this brings us back to private mobile networks, or NPNs.
As we noted, these are built using the same technologies as PLMN networks. That is, one of the generations of tech we know as 2G, 3G, 4G or, of much more interest to us today, 5G – and, in the future, 6G.
By leveraging these technologies, the builders and operators of NPNs can use equipment and solutions that have been proven in their PLMN peers. They can also tune performance to meet specific needs. We will explore why they are of growing interest in another Tech Tip, but there’s a key point that we need to explore before concluding this article: spectrum licensing.
License to…build NPNs
Again, we’ve covered this before. Briefly, spectrum — the radio frequencies used for carrying mobile signal and data — have been tightly controlled by an international body, the ITU-R (International Telecommunication Union, Radio Communication Sector – a unit of the UN). That’s to avoid interference from different users of the spectrum. The frequencies are determined by the ITU-R and then national regulators decide how they should be shared in each country.
Access to this spectrum has been tightly controlled. However, that’s changing. Many regulators, seeing the potential of 5G to serve very specific industrial or public purposes have withheld spectrum for use by NPNs. Now, this is where the terms WAN and LAN become relevant again.
A mobile network operator is usually obliged to deliver coverage across the whole country, with tight targets written into the licenses they are granted. However, many 5G-enabled private applications are only required in a specific location.
Hence, NPNs can be built for a site of a few hundred square metres, for example. The NPN owner may have several sites, so may seek licenses for a number of such limited zones, in different locations. An NPN, then, is also like a LAN (where applied only to one location), or a WAN (when applied to several locations, serving the same need).
The thing to remember is that, when we talk about private mobile networks, we must consider all the caveats around tech, spectrum, licensing and access and think of them as islands surrounded by all kinds of other networks, public or otherwise.
Telecom26 – how do we help?
Many companies and organisations recognise the potential that NPNs can offer. They — not MNOs — are best placed to understand the kinds of performance that they need to achieve within the NPN. However, translating business KPIs into network KPIs to ensure that the NPN delivers is a different matter.
That’s where we come in. We have the experience and technical know-how to help any organisation deploy the right kind of NPN – optimised to meet business and organisational goals. Of course, large MNOs may also help – but they may only be focused on multi-national corporations, not the needs of smaller businesses.
Where spectrum is available from the regulator, we can help you secure the frequency you need for the intended location. We can provide the radio, transport and core, build the network for you, and operate it so you can meet your goals — and we can even help determine how you enable access to your network — together with our SIMs for local device connectivity, protected by our advanced security.
Best of all, we take care of the mobility part, while you focus on the outcomes you seek from the NPN. It’s a partnership that blends our expertise with yours, bringing NPNs to any organisation that needs them. Your network, how you want it – delivered and managed by us with our connectivity.
Why not talk to us and see how we can help?
