Private 5G Network Architecture

Private 5G is a mobile network which is actually the same as a public 5G network, but Private 5G network allows the owner to provide priority access or control for its wireless spectrum. 

Built on 5G technologies, Private 5G network is a local area network which is used for dedicated wireless connectivity within a particular area. Private 5G offers ultra low latency and incredibly high bandwidth connections that can support artificial intelligence – driven applications which serve as an exploding number of sensors and endpoints. 

Private 5G network can be independently managed by its owner, and the owner has the authority to control every aspect of the network, like priority schedule, resource allocation, security, etc.

Private 5G Network Architecture Explained

A Private 5G network mainly designed for a single organization, like for an industrial enterprise. Within a particular or defined premise like plant and campus, the Private 5G network provides network services to devices like auto-guided vehicles, mobile robots and several sensors. 

In a Private 5G network, there are several factors which need to be considered like spectrum, the owners and operators, and the trust level between private and public network operators. 

According to 3GPP 5G, Private 5G networks have two basic forms, i.e., stand-alone deployment and public network integrated deployment. 

There is also a O-RAN which stands for Open Radio Access Network alliance has recently introduced the O-RAN concept, which can organise a cost effective and agile RAN by adopting open interfaces, open hardware, and open source. 

This framework will mainly be used to maximise the use of common-off-the-shelf hardware and merchant silicon to minimise the installation cost of the private network. O-RAN may be a valuable proposition to build small, customised Private 5G networks which are not dependent on a single vendor.

Private 5G Network Deployment Modes

Below are the two different types of deployment for Private 5G Network:

1. Stand-Alone Deployment

In Stand-Alone deployment, a Private 5G network is deployed as an isolated and independent system without dependence on a public network, which is known as a stand-alone non-public network as well. 

All network functions of a stand-alone Non-Public Network are confined in the logical perimeter of the particular defined regions. There are basically three facts that manifest the independence between a stand-alone Private 5G network and a public counterpart. 

The first fact is that the Private 5G network uses an unique identifier which is completely independent of that for a particular network, while the second fact is that the private spectrum is assigned to the Private 5G network, and the third fact is full deployment of a 5G system which includes the RAN and the core network that exist within the logical perimeter of the Private 5G network.

2. Public Network Integrated Deployment

In Public Network Integrated deployment, a private 5G network is deployed with the help of a public network. Both the networks i.e. public and private networks are not physically isolated and when we compare it with the stand-alone deployment, this deployment has lower customization, self-control and security. 

This kind of non-public 5G networks can be further subdivided into three cases. 

Below are the three categories of Public Network Integrated Private 5G network Deployment:

1. Shared RAN

In this scenario, the Private and Public 5G network share part of the RAN, while other network functions are still different, and all data flows of the non-public 5G networks are restricted to the local area. For making the model simple, there is only a single BS for the shared RAN on the particular defined premises. 

2. Shared RAN and Control Plane 

The non-public 5G network shares part of the RAN with the public network. The network control tasks are always conducted by the public network. While all the traffic flows of the private network still remain within the particular defined area. This approach is mainly used for creating logically independent networks over the same physical infrastructure. 

3. Hosted by the Public Network

In this case the private network is completely hosted by the public network. In this approach the traffic from both the public and private portions are outside of the particular defined premises. All the data flows of the non-public network are guided to the public network through the shared RAN. 

Requirements For 5G Private Networks

For the public safety segment and essential industrial application private networks are built to provide continuity of service even when unpredictable and undesirable events occur. 

In practice, ensuring continuity of service in critical networks means building secure networks with high availability and reliability.

Private 5G network main critical capability requirements are as follows:

Source: https://www.ericsson.com/4af95a/assets/global/qbank/2019/12/18/5g-private-network-requirements

1. Availability

High availability means that the end user can always use the service whenever required. In practice, the network must be built so that downtime is virtually zero and if any system requires maintenance then that can also be controlled. This may include robust solutions and redundancy constructions of critical elements.

2. Reliability

Reliability means the capability of transmitting a given amount of traffic within a predetermined duration with high success probability. It offers sufficient network coverage and capacity, as well as robust handover functionality.

3. Interworking 

Interworking is an important capability with public networks. Many emergency services like ambulances need service continuity while moving from one network to another network, for instance from a private network to a public network.

4. Quality of Service  

Quality of service consists of latency, throughput, jitter packet drop rate and more. A dedicated spectrum private network offers the possibility to control each. 

5. Security 

Private networks are expected to provide full end-to-end security that ensure information, infrastructure and people are protected from threats. There are basically three main security principles that should be preserved: confidentiality, integrity and availability.

Opportunities and Challenges in Private 5G Network

In some organisations some networks like ethernet, WiMAX, Bluetooth,etc still fail to resolve key customer issues that create  negative impact on business and operations. That’s why they require more reliable and capable networks.

Opportunities and Challenges that are driving this migration from previous network towards private 5G networks are as follows:

  • A need for better data security, to make critical assets and to dynamically customize the network in challenging situations.
  • Data-heavy use cases for new augmented reality(AR), virtual reality(VR) and HD video based applications, for remote inspection, monitoring and surveillance.
  • Continuous investments and innovations in 3GPP technologies, that makes them more attractive to organizations and governments that were not previously addressable.
  • Existing narrow band mission-critical networks reaching the end of their life cycle.
  • Industry 4.0-related productivity gains through more flexible production, increased mobility and organization connectivity.