## 2 Private and Community 5G Networks  
### 5G Non-Public Networks and Urban Deployments  
The use of 5G technologies to support deployments beyond traditional MNO networks opens a wide range of applications and scenarios for wireless technologies. One area that has seen massive interest to date is in support of IoT-based deployments and particularly around Industry 4.0. The next generation of industrial services, from manufacturing to logistics, are being designed to heavily incorporate data networks to support a wide variety of sensor and communication requirements, where traditional wired technologies are either too expensive or infeasible to deploy on this scale. For example, even in a moderately sized factory site of 1-2 km\({}^{2}\), the sheer scale of connectivity requirements would introduce significant problems, notwithstanding the need for flexibility in the case of reconfigurations and the potential to deploy this in a challenging or hazardous environment. As such, the use of 5G wireless technologies in this space provides many advantages including reduced cost and complexity while still providing good bandwidth and responsiveness. In the 3 GPP scope, these are called private networks or non-public networks (NPNs) [3] as opposed to the traditional Public Land Mobile Networks (PLMNs). These NPN 5G deployments could make use of a combination of shared and private base stations and backend infrastructure through slicing to provide network capacity solely provisioned for the use case. This area is still under active research in academia and beyond but an overview of some potential solutions are described here to provide context for our work. In order to support 5G NPNs, various scenarios have been envisioned whereby the 5G Core (5 GC) can be provisioned and controlled locally or remotely, or through some combination of the above [4]. Essentially, both the Control Plane (CP), which provides device and network control such as access control and management, session management, mobility management and policy management, and the User Plane Functions (UPF), which deal with data routing and forwarding, need to be provisioned for the user in order to provide a 5G service [5]. On the one hand, an operator might choose to deploy just the gNB locally (or virtually through slicing) to save CAPEX and OPEX overheads and handle most of the backend functionality remotely, which greatly simplifies operation at the potential cost of some performance overheads. Conversely, a full local deployment would certainly be more expensive and complex to operate but would be solely provisioned and therefore more performant [6]. Moreover, the heterogeneous nature of available RAN technologies in 5G provides a powerful mechanism to support a range of devices and applications, from LoRa sensor devices, through to 4K streaming or VR-type users. In addition to 5 GNR, an operator might make use of some version of LTE in addition to Wi-Fi, mmWave and other technologies to provide appropriate coverage [7]. Through splitting the RAN into a Central Unit (CU) and multiple Distributed Units (DUs), different levels of control can be applied. These functional splits dictate where in the stack the separation between the CU and DUs occurs and potentially offer a great deal of flexibility in terms of how sessions are managed in the RAN, from a very 'low' traditional split up to more innovative but complex 'high' splits [8]. Another interesting deployment area for 5G is in public networks deployed by and for a community [7]. Such networks can, for example, be setup by a local government or organization and provided to members where MNO coverage is not available or suitable or focused around a specific use case that meets a public need. In this case, there is again a wide range of potential deployment models that could be adopted depending on the specific circumstances. An organization might apply for a specific portion of the available spectrum in their area to deploy their own base stations, or adopt another unlicensed solution.