Mark Waddell, BBC R&D, and Douglas Allan, Neutral Wireless
The UK’s current public mobile network ecosystem is typically dominated by just two or three so-called ‘tier-1’ radio equipment manufacturers whose solutions offer little scope for interoperability with other vendor systems. Inevitably, vendor lock-in results which inhibits growth in market competition and the potential to achieve reductions in costs. Arguably, vendor lock-in can also weaken the resilience, sustainability, and indeed security of our telecoms critical national infrastructure.
An alternative to this status quo is Open RAN, which is an initiative intended to diversify the supply chain by defining standardised interfaces between base station components, as defined by, for example, the O-RAN ALLIANCE. The intention is to improve the security and diversity of the supply chain and optimise the efficiency of the interfaces.
Standardised interfaces are likely to be ingredients of next generation systems in 6G and allow intelligent control of mobile networks using AI.
Our ON-SIDE project is part of a UK Government funded Open Networks Ecosystem initiative. It is primarily concerned with the technical, operational, and commercial impact of private 5G networks on use cases across several market verticals – including investigating the practical pros and cons of Split-8 vs Split 7.2 O-RAN architectures. The different approaches, based on how the 5G stack is partitioned, does offer some interesting potential computational benefits. But how these might be translated into actual cost and performance benefits requires further quantification – and will be dependent on specific deployment scenarios. Our technical and performance observations will be highlighted in a future post.
Putting to one side for a moment the technical architectural differences between Split-8 and Split 7.2, the fundamental principles behind open networking are something that the ON-SIDE project and partners have already robustly proven. The coronation of King Charles III and Queen Camilla in 2023, and last year’s summer Olympic Games in Paris, both reached video screens and audiences world-wide thanks to pioneering work on private 5G networks by ON-SIDE partners at the BBC, Cisco, and Neutral Wireless. These large-scale, extremely high-profile broadcasts were delivered using a system integrated approach and solution comprising multi-vendor subsystems: bringing together proprietary and market-ready technology. The success of these deployments, effectively demonstrated the viability, necessity, and possibilities of pop-up, open networks operating in regulated shared spectrum bands.
We’re continuing to build on these success stories — and broadening the slate of applications for this open approach to networking. The team at Neutral Wireless has created an evaluation platform that enables a practical exploration of some of the benefits of its O-RAN architecture for private, standalone 5G networks. Elsewhere, the BBC has been testing Cisco’s portable 5G system, while academics at the Universities of Strathclyde and Glasgow continue to develop O-RAN solutions and scale the security framework for O-RAN enabled private networks. Our results, so far, are starting to test and quantify the purported promises that O-RAN architectures will enable a more open, efficient, and cost-effective RAN solution for large-scale public and private networks alike, and whether any such benefits will also be cost-effective in, arguably, smaller-scale, high-performance use cases like live broadcasts and connected stadia.
With 5G coming of age, and 6G on the horizon, the ability for operators and end users to utilise an open networking ‘mix and match’ approach may be key to rolling out commercially viable current and next-generation comms networks. As the technology continues to mature, we can expect more vendors to enter this open ecosystem, providing increased choice and diversity to RAN system integrators and network operators — and, ultimately, an improved offering to the end user.
The past few years have featured several exciting success stories for Private 5G, particularly in the broadcasting sector. Companies such as Neutral Wireless, Cisco, and the BBC, aided by academic collaborators such as the University of Strathclyde’s Software Defined Radio lab (StrathSDR), have rolled out ambitious and ground-breaking deployments such as for HM King Charles III’s Coronation, or for elite global sporting events.
But if you’re coming to these stories late, you may be wondering what all the fuss is about. You might be asking yourself… “What is Private 5G?”.
What is Private 5G?
In a nutshell, a Private 5G network features most of the same component parts as a public 5G network. However, Private 5G networks are often deployed at a smaller scale, and with a different end goal in mind. Rather than providing ubiquitous 5G coverage to be shared amongst the general public, Private 5G instead focuses on delivering dedicated, high-performance connectivity for specific use cases.
Private 5G also comes with an inherent level of security. Just like a relevant SIM card is needed to access a particular public cellular network, the only devices able to attach to your Private 5G network are those which you have provided with SIM cards for secure authentication.
This means that rather than sharing network resources with several thousands of people (think of all those failed New Year’s Eve phone calls), your mission- and business-critical applications can rely on dedicated resources. And since you are in control of the network, you can also configure how those resources are allocated.
A Private 5G network can be tailored towards a specific use case, with the relevant communications resources configured for higher upload speeds or ultra-low latencies, depending on what is required. This flexibility can be particularly important for applications featuring video cameras or sensor data, where a focus on upload speeds is a priority (in contrast to public cellular networks that are configured to favour download traffic).
Private 5G Building Blocks
5G networks of course consist of several hardware and software components, with a wide variety of standardised interfaces and a lifetime’s supply of acronyms. But considered at a high level, Private 5G networks consist of just a few need-to-know building blocks.
User Equipment (UE) refers to the end devices that will connect to the network via an attached SIM card. A UE will feature a 5G modem that allows the transmission and reception of 5G signals. Some examples of common UEs are smartphones, video/security cameras, or sensors.
Antennas are used to transmit and receive radio-frequency (RF) 5G signals. 5G antennas can either be omni-directional or directional. Omni antennas will provide 360-degree coverage, whereas directional antennas will provide narrower coverage in a specific direction (often to greater distances). A 5G antenna will be connected to an associated radio head via RF cables.
Radio Heads are 5G radio transceivers responsible for broadcasting the wireless RF signals that are transmitted over the 5G network via connected antennas. A radio head and antenna pair (and associated coverage area) is referred to as a 5G “cell”. In public networks, cells are usually deployed on top of tall masts at elevated site locations, or on city infrastructure. But this does not have to be the case with Private 5G. Radio heads are connected by fibre optic cables to a baseband unit, and this interconnect is often referred to as the “fronthaul” link.
A Baseband Unit (BBU) generates/processes the signals that are transmitted/received by connected radio heads, translating useful data into radio signals and vice versa. In 5G terminology, a BBU can be referred to as a gNodeB, or gNB. A 5G network can consist of several BBUs, which must all be connected back to a single 5G core. Collectively, the portion of a 5G network containing the antennas, radio heads, and BBUs is referred to as the Radio Access Network, or the RAN.
The 5G Core can be thought of as the brains behind a 5G network, and is responsible for device authentication, mobility management (as devices travel between cells), and connectivity to external networks. The connection between the BBU and the 5G Core can vary depending on the specific 5G architecture. In some cases (such as for smaller deployments), the BBU and 5G Core can be deployed on the same physical hardware. Otherwise, they can be connected via fibre optic cables, and this interconnect is often referred to as the “backhaul” link.
Backhaul Connectivity (Optional) In the context of a Private 5G network, “backhaul” is one of those tricky terms that can mean several different things. Traditionally speaking, it refers to the BBU-to-5G-Core interconnect, as mentioned above. However, “backhaul” can also be used to refer to the connection between the 5G core and an external network – such as an organisation’s wider LAN (sometimes referred to as the network “edge”), or public internet. From this perspective, backhaul can be thought of as the “internet source” that UEs over a wider area can access wirelessly, via 5G. This can be provided via several options such as fibre or ethernet, point-to-point microwave, or LEO satellites.
Access to 5G Spectrum. All 5G networks require a spectrum licence for legal transmission. Ofcom’s Shared Access Licence scheme, introduced in 2019, has allowed the UK to become a world leader in Private 5G innovation by allowing affordable access to the upper-n77 frequency band. The ONSIDE project looks to build on this foundation to make full use of the available spectrum, through improved accessibility to (and understanding of) Private 5G and exploring possible routes for quick and dynamic spectrum licensing.
All 5G networks will contain each of the above building blocks, in some fashion. But there can be significant differences in how each of these component parts is implemented.
To give a relevant example – a key area of development in recent years is the concept of software virtualisation. Traditionally, many of the aforementioned building blocks would exist as dedicated hardware implementations. However, virtualisation allows for the same functionality to be achieved in software, allowing for virtualised BBUs and 5G Cores to be deployed on high-performance server grade compute platforms.
Another important consideration is how all of these pieces fit together. Or, in other words, the network architecture.
Putting it all Together – Private 5G Network Architectures
Traditional RAN Architecture
A “traditional” 5G RAN architecture will be largely similar to the configuration illustrated in Figure 1. In this case, the network components are connected mostly as described above, with the BBU and the 5G Core existing on physically separate platforms. Whether these are implemented on dedicated hardware or as virtualised software implementations makes no difference to the architecture itself, but in the latter case this might also be referred to as a “virtualised RAN”, or vRAN.
Figure 1: Illustration of a Traditional RAN Architecture, in this case with a cloud-based 5G Core
In the above example, a cloud-based 5G core implementation is shown. This type of architecture is often desirable for large-scale or multi-site deployments – especially those deployments that need to be tightly coupled into existing IT and business management systems. Cloud-based 5G Cores (such as those offered by ON-SIDE partner Cisco) can offer an “as a service” delivery platform serving people, things, and places.
However, for smaller-scale (or pop-up) private deployments, there can be a benefit to deploying the 5G Core locally. Platforms such as Cisco’s Private 5G solution, or Neutral Wireless’s Private 5G Lomond NIB, can ensure local (edge) data can remain local. Access to a local 5G Core can remove any dependency on costly fibre runs back to organisational premises, or even public internet connectivity.
Consolidated RAN Architecture
In some cases – particularly for vRAN implementations – there is scope for various network components to be deployed on the same physical hardware, or within the same physical casing. This type of consolidated 5G RAN architecture often features what have become known as “Network-In-a-Box” (NIB) style products, such as the Neutral Wireless Lomond NIB.
An example of a NIB-based consolidated RAN architecture is illustrated in Figure 2. Note that this is just one example of a consolidated architecture, of which there are several variations. Other examples could include cloud-based 5G Cores, or radio heads with integrated antennas (a practice that is somewhat common for low-power, indoor radio units).
Figure 2: Illustration of a Consolidated RAN architecture
At a glance, it should be obvious that this type of architecture can result in drastically simplified deployments, as illustrated in Figure 3. As such, consolidated 5G network architectures are perhaps inherently more suited to pop-up style deployments such as for events, festivals, or news gathering broadcasts.
Figure 3: An example of a consolidated Private 5G architecture for live broadcasting. Here, two options are presented for backhaul to the production studio (via long-distance fibre optic, or LEO satellite).
ORAN Architecture
Open RAN, or ORAN, is a proposed non-proprietary RAN architecture that seeks to diversify the 5G network supply chain through the definition and promotion of standardised interfaces. The ultimate goal of ORAN is to enable complete interoperability of 5G networking components from different vendors.
The ORAN architecture (illustrated in Figure 4) seeks to split the functionality of the BBU, and in some cases to offload some of the responsibilities of the BBU to the radio heads (referred to as Remote Radio Units or RRUs in ORAN nomenclature). In ORAN, the BBU is split into two separate units known as the Distributed Unit (DU) and the Centralised Unit (CU). This necessitates a new interconnect between the DU and CU, which is referred to as the “mid-haul” link.
Figure 4: Illustration of an ORAN Architecture
There are several numbered split architectures within ORAN, which correspond to different areas of split responsibilities across the RRU, DU, and CU. Within the ON-SIDE project, the BBC, Cisco, Neutral Wireless, and the University of Strathclyde are exploring the Split 7.2 architecture, and are comparing the achievable performance to traditional and consolidated network implementations.
So… Which is Best?
The honest answer, and the only answer that can provide an end customer with the best performance, is that “it depends”. Different architectures of course come with different benefits and drawbacks, and the extent to which these will be beneficial or costly depends on the targeted use cases.
Figure 5: Comparison of different 5G RAN Architectures. Note that in most cases, the 5G Cores could be either local or cloud-based.
A driving force behind the ON-SIDE project is the desire to develop Private 5G solutions that are more accessible to a wider range of end-users. By engaging with key stakeholders in various sectors, the ON-SIDE consortium aims to increase adoption rates by understanding and addressing the challenges and requirements of specific customers.
The flexibility of Private 5G and its associated architectures can be a powerful tool in tailoring a network to meet those requirements. By thinking of a Private 5G network as a series of building blocks rather than a singular entity, bespoke deployments can be undertaken to provide optimal value and performance.
These could involve portable, all-in-one Network-In-a-Box style solutions or disaggregated networks that can take advantage of existing fibre infrastructure in locations such as TV studios, sports stadia, or outside broadcast compounds. Even battery-powered networks are a possibility – allowing for robust connectivity at remote locations, or those that are difficult to access.
In any case, the key is that the use case should inform the architecture, rather than vice-versa. This is the approach taken by the ON-SIDE partners: working together to understand the key operational and business requirements of use case stakeholders, before designing tailored, technical solutions to meet those needs.
In early November, the ON-SIDE team gathered at the BBC Studios at Pacific Quay in Glasgow to test and measure the performance of various 5G architectures and video encoding.
As part of the project, we are investigating the use of 5G networks in a broadcast studio environment. While the BBC has deployed 5G networks to support production in the past, notably at the King’s Coronation in 2023, these deployments have focused on a contribution use case where multiple user devices are connected to a network as independent devices. As there is no interdependency between these user devices and other equipment, they have different requirements around latency, and they often use heavy compression to move audio and video signals over the network.
In a production studio environment, we have different requirements: we have more stringent latency targets, and the video quality needs to be as high as possible. This is in order to be able to inter-cut the output of a radio camera with other sources such as cabled cameras.
There are other considerations too: we need to be able to control a camera and communicate with the operator, as well as carry signals to and from ancillaries such as autocue or microphones.
Currently, these cameras are usually configured using dedicated radio links for each camera on a unidirectional path with dedicated spectrum for each unit. Add on all of the control and communication requirements, which also have dedicated radio resources, and we have a complex ecosystem that requires specialist equipment and engineering.
As part of the ON-SIDE project, we wanted to see if we could use private 5G networks to support wireless camera operations in a studio environment. This has the advantage of a single IP-based bidirectional configuration which means we can be more efficient in the use of spectrum. For a given spectrum channel of sufficient bandwidth, we can, in theory, operate multiple cameras and associated equipment.
In order to determine if 5G private networks could meet our requirements, we needed to look at several different aspects of the workflow. To address the latency issues, there are two main considerations:
the time taken to encode and compress and then decompress a video signal;
the time taken to carry this data over the network reliably.
For the contribution use case, where latency is not as strict, we can take time to compress the video and send it over the network and allow for any packet loss or retransmission of data. Typically, this is between 1 and 2 seconds.
In the studio environment, we need to aim for a latency of less than 100 ms. This is to enable not only inter-cutting of content but also a near-instantaneous response to any control signals to the camera. The latter is particularly challenging as we need to factor in round-trip time, not just the glass-to-glass latency.
For the testing, we set up three independent private networks: a Cisco core and an ORAN solution running in the N77 spectrum band and a Neutral Wireless Lomond NIB running in the N40 spectrum band.
Spectrum was a mix of ON-SIDE and BBC spectrum secured via Ofcom’s current spectrum licensing systems, and one of the aims of the project is to identify how we can streamline this process.
We also ran various encoders from several manufacturers at different bit rates and recorded the output so that we can do some later analysis of the encoder performance.
We measured the radio performance at dedicated points around the studio for each system and collected data for each of the networks.
We also configured camera control and other devices, such as mobile phones, to act as monitors or comms units.
The full results are currently being analysed and will form part of the output documentation of the ON-SIDE project.
The project team would like to express their thanks to BBC Scotland, Sony, and Haivision for the loan of the studio, encoders and cameras that enabled this testing.
From pioneering private 5G solutions to advancing immersive training and spectrum monitoring technologies, the year has been marked by innovation, collaboration, and groundbreaking successes. Here are some highlights from our partners’ achievements and their plans for 2025.
Cisco: Driving Digital Transformation
Cisco, in partnership with Neutral Wireless, has developed a portable 5G system that underwent extensive interoperability testing. This system was successfully sent to the BBC, where it played a pivotal role in wireless camera testing, training, and research.
Additionally, Cisco and Intel have staged equipment at Logicalis labs, preparing for a comprehensive deployment at the port of Liverpool operated by Peel Ports.
Peel Ports Group in Liverpool is a hub for the UK’s container trade and a critical gateway for international shipping. With significant investments in infrastructure and technology, the Port of Liverpool stands at the forefront of the global logistics industry. Cisco, Intel and Logicalis, in collaboration with the port, are deploying a private 5G network to tackle connectivity and communication challenges.
This innovative network aims to support advanced use cases such as automation and remote crane operations, vessel monitoring, enhanced CCTV, and ubiquitous mobile connectivity for port staff, ensuring seamless operations and safety. Peel Ports Group’s commitment to efficient, sustainable logistics underscores the prestige of this collaboration and its significance for regional economic growth.
Damian Cross, Head of Containers Technology and Automation Strategy said: “We’re delighted to be working with Cisco, Intel and Logicalis to enhance the Port of Liverpool’s network as we seek to drive further innovation across our containerised cargo operations.”
Looking ahead, Cisco’s priorities include activating portable 5G systems across the UK and deriving insights from live deployments, such as the port’s digitisation efforts.
University of Strathclyde: Pioneering Spectrum Management and Open RAN Solutions
The University of Strathclyde has developed a proof-of-concept system for demonstrating and evaluating spectrum management approaches that could help to make private 5G networks more easily deployable in future. It has also developed innovative spectrum sensing technology for incorporation into the spectrum management proof-of-concept system, and has worked with Neutral Wireless to show how such spectrum sensing could be built into radios to aid network deployment and achieve more effective utilisation of shared spectrum.
The Strathclyde team has also been working with the BBC and Neutral wireless on building and evaluating a number of Open RAN solutions, and this work is generating a number of Open RAN-related learnings.
In addition to the above technology development and evaluation activities, the team has been supporting project partners on deployment testing and evaluation of private network use case opportunities.
In 2025, Strathclyde will be further developing and refining its sensing-enabled spectrum management proposals and contributing to the sharing of project learnings, and will continue to support other project partners to develop private 5G opportunities across various application areas and use cases.
University of Glasgow: Transforming Education Through Technology
The University of Glasgow (UoG) has leveraged ON-SIDE to advance immersive training solutions, focusing on clean room environments like the James Watt Nanofabrication Centre. Key achievements include the development and deployment of a VR Immersive Training Framework, the design of comparative studies between private 5G and other technologies, and initial trials in clean rooms. UoG also leads a comprehensive security study for shared spectrum private networks, addressing critical challenges in protecting network integrity and spectrum licensing.
For 2025, UoG plans to compare next-generation Wi-Fi standards with private 5G to explore cost-effective alternatives. The university will continue its focus on user experience studies and scaling the security framework for ORAN-enabled private networks.
Neutral Wireless: Innovating Spectrum Monitoring and Stadia Applications
Neutral Wireless made significant strides in spectrum monitoring by developing a front-end capability using AMD RFSoC devices. This innovation allows real-time RF environment sensing, which could revolutionise spectrum licensing by regulators such as Ofcom. The integration of spectrum sensing with their 5G radios offers dual functionality, enhancing deployment efficiency and reducing interference risks.
In addition, Neutral Wireless collaborated on stadia use cases, including two deployments at a premier Scottish football stadium. These efforts have informed broader applications of private 5G in high-density environments and media production.
Their 2025 goals include showcasing live private 5G operations in stadia, addressing co-channel interference challenges, and advocating for faster RF licence turnarounds through real-time spectrum sensing.
Insights from 2024
Across the ON-SIDE community, a recurring insight is the transformative potential of private 5G in addressing diverse challenges, from immersive training to high-demand environments. Partners emphasise the importance of collaboration, proactive security strategies, and user-centric design to overcome technical and adoption barriers.
Looking Ahead to 2025
The year ahead promises continued innovation, with partners focusing on real-world deployments, comparative technology evaluations, and expanded use cases. The ON-SIDE project remains a testament to the power of practical co-innovation in advancing digital transformation across industries.
We celebrate these achievements and look forward to another year of groundbreaking work. Stay tuned for updates as ON-SIDE continues to lead in technological innovation and impact!
