What is a private network?

March 24, 2022 | Over the next few weeks, I am going to use this column to explain and discuss some of the common terms used in the wireless industry today, terms that oftentimes are either misunderstood or not explained in sufficient detail. First up: private networks!

We use private networks every day. Only Comcast subscribers get the modems that are authorized to access the Xfinity network; only Verizon mobile subscribers with the appropriate SIM cards and IMEIs can access that 4G/5G network; only employees of ABC Corp. with authorized logins and devices can access the ABC Wi-Fi network.

But these are not private networks in the cellular world. 5G New Radio (3GPP Release 15 and 16) introduced the “non-public network” (NPN) which can either be owned/operated on a standalone basis by a “non-public network” operator. The 3GPP also specifies that a NPN can also be integrated with a public network (i.e., a mobile operator’s network) – a public network integrated (PNI-NPN). Prior to Rel-15/-16, carriers created private networks via closed subscriber groups of devices/users and/or private access point names (APNs).

In 5G terms, though, a private cellular network can either be a standalone NPN or a PNI-NPN. Most of the time, the term “private (cellular) network” refers to the former, but it can also refer to the latter.

In the U.S., the CBRS band is important for several reasons, but the critical one is this: Enterprises do not need a mobile network operator to create a private cellular (4G/5G) network. If you don’t think this is a big deal, then look at the in-building (indoor) small cell market – small cells and distributed antenna systems (DAS), in particular. Prior to CBRS, those networks required an RF signal source which could only be obtained with the direct involvement of an MNO (e.g., AT&T, T-Mobile, Verizon, etc.) because those carriers owned all the spectrum.

Now, with CBRS in the U.S. (and other countries have their own shared spectrum), iGR believes that most private cellular networks will be owned and/or operated by an enterprise, a NPN operator (like a WISP or other third party) or even a mobile operator. Here are a few examples of recent announcements that might help illustrate:

– Carrier-led: Verizon and Celona have partnered to provide a turnkey private networking solution that uses Verizon’s On Site LTE and 5G network with Celona’s products (SIM cards, indoor/outdoor radios, software for network management, etc.). In this example, the network layer is Verizon’s licensed spectrum rather than CBRS.

– Hyperscaler-led: AWS Private 5G provides enterprises with a package of small cell radio units (which use CBRS), edge servers, SIM cards – basically everything the enterprise would need to set up its own private network. Once connected to the Internet, AWS would run the network from its cloud core. iGR believes that the hyperscalers (AWS, Microsoft, Google) will make huge inroads with enterprise private networks.

– IT Equipment-led: Cisco’s Private 5G solution is, essentially, an extension of its Wi-Fi and other networking equipment. With Cisco’s solution, the enterprise obtains the private network “as a service.” The physical equipment is coming from partnerships with JMA and Airspan, but the core network is Cisco’s own.

– Systems Integrator-led: Enterprises often turn to SIs for assistance in implementing, adding or otherwise transforming their systems. Private cellular networks are a great way to adopt new processes and/or add Internet of Things (IoT) devices to spur digital transformation (more on that in a future post). This can be a complex undertaking in which SIs can assist.

iGR will soon publish a series of reports on the inbuilding cellular market; enterprise private networks are an integral piece. Private cellular networks are the new small cells…and edge compute…and Open RAN…and cloud core…but with one key difference: Nobody needs the carriers to make them work.

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