User Stories

How OpenStack Powers BT Group’s 5G Network Transformation

Together, Canonical and BT have rolled out OpenStack-powered 5G access to over 75% of the UK population, marking a significant achievement in the country’s mobile connectivity landscape.

April 16, 2025
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The future of mobile network infrastructure is shifting towards open-source solutions, and BT Group is leading the charge in the UK’s transition to ubiquitous 5G coverage. As part of this transition, BT Group required a new infrastructure capable of supporting the distributed architecture of 5G and enabling network function virtualization (NFV). To meet these demands, the company turned to open-source solutions, choosing Canonical’s OpenStack to help build and scale its 5G network. The partnership has resulted in the successful deployment of 5G access to over 75% of the UK population, marking a significant achievement in the country’s mobile connectivity landscape.

The Challenge

BT Group, which operates the UK’s largest mobile network through its subsidiary EE, plays a critical role in providing connectivity for millions of people across the country. With users’ expectations for mobile networks constantly rising, BT Group faced increasing pressure to stay ahead of demand while continuing to deliver the highest level of performance and reliability.

The rollout of 5G Core began in 2019, introducing a new set of challenges for BT Group. Unlike previous generations of mobile networks, which relied on centralized, hierarchical architectures, 5G required a distributed, service-based architecture (SBA). The decentralized nature of 5G involves decoupling network functions into smaller, independent services, allowing for a faster and more resilient network. This shift necessitated a complete overhaul of BT Group’s infrastructure to support virtualized network functions, which required substantial changes to both hardware and software.

Gary Roberts, Director of Network Cloud at BT Group, explained, “The challenge was how to bring real NFV onto a common platform. Before this, any forays into virtualization had been on a bespoke basis. At the same time, we didn’t want to be beholden to proprietary solutions. We wanted to move into a more open-source world for the support, community, and price.”

The Solution: OpenStack

BT Group’s decision to embrace open-source solutions led them to Canonical’s OpenStack, a leading open-source cloud computing platform. OpenStack would allow BT Group to virtualize its network functions and separate them from the underlying hardware, enabling multiple applications to share the same physical resources across data centers. This virtualization would also enable continuous integration and development, faster software updates, and greater scalability—all critical to the success of 5G.

However, transitioning to OpenStack was not without its complexities. Given the scale and critical importance of the 5G Core network, BT Group needed expert guidance to deploy and manage OpenStack efficiently. With over 20 years of open-source expertise and extensive experience with OpenStack deployments, Canonical was the ideal partner.

Canonical helped BT Group design and deploy multiple cloud environments to support 5G control and data plane use cases, along with associated network management requirements. The company used Canonical’s telco-grade OpenStack distribution, which minimizes the cost and complexity of operations through advanced automation. Canonical’s infrastructure solutions allowed BT Group to take full control of its infrastructure, which had previously been vendor-managed.

Training and Internal Empowerment

A key element of BT Group’s move to open-source technology was its desire to gain more control over its infrastructure. To enable this shift, Canonical provided extensive training to upskill BT Group’s team, equipping them with the necessary knowledge to operate OpenStack effectively.

Nick Heatley, Network Architect at BT Group, remarked, “Open technologies have allowed us to use common tooling to automate the layers, and open, standard observability is a game-changer for operations in terms of full-stack visibility.”

With these advancements, BT Group was able to move away from proprietary solutions, embrace an open-source model, and improve its ability to manage and scale the 5G network independently.

Partnership and Success

The collaboration between BT Group and Canonical proved highly successful. Despite the complexities involved in such a large-scale project, the two teams worked closely to address any issues as they arose. “Whenever we came across a problem, Canonical was absolutely front and center,” Gary Roberts noted. “The attitude was always ‘let’s work on this together.’ It was a real collaborative exercise.”

The results were evident: by 2023, BT Group and EE had successfully made 5G available to over 75% of the UK population. “In the last year, we’ve moved the entire mobile base for EE onto this infrastructure. So if you’re on EE, you’re on Canonical,” said Roberts.

The shift to 5G Core has unlocked a level of agility and scalability that was previously unattainable. With the new distributed architecture, BT Group can update software and scale the network on demand, rapidly developing and deploying new services. This flexibility enables BT Group to stay ahead of growing customer demands, even as the network continues to expand.

Impact on BT Group and its Customers

One of the most profound impacts of this transformation is on the customers who benefit from the improved network. For example, 5G is a game-changer in high-density areas, such as sports stadiums, where it historically has been difficult to provide sufficient network capacity. With 5G and dedicated on-site network boosting systems, BT Group can now deliver seamless connectivity to tens of thousands of people in the same location simultaneously.

Watford Football Club became one of the first stadiums to introduce 5G for its fans, providing an enhanced fan experience. John Parslow, a Watford supporter, shared his excitement: “For as long as I can remember, it was always impossible to upload and share videos from the stadium. But now, they’ve introduced 5G, and it is allowing me to connect with my fan group around the world as if they were in the stadium with us.”

Despite the significant technological shift, BT Group’s network performance has not suffered. In fact, it has only improved. In 2023, EE was named the UK’s Best Mobile Network for the tenth consecutive year, a testament to the success of the 5G transformation.

BT Group’s journey towards a fully virtualized, open-source 5G network powered by Canonical’s OpenStack demonstrates the power and potential of open-source solutions in large-scale infrastructure projects. The partnership has not only revolutionized BT Group’s network capabilities but has also set a new benchmark for mobile network operations, providing better performance, scalability, and customer satisfaction. As open-source technologies continue to evolve, BT Group stands at the forefront of innovation, ensuring that the UK’s mobile connectivity remains world-class.

Check out the full case study from Canonical.

Allison Price
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