The path towards disaggregation of mobile radio access networks

A debate on the impact of open and virtualised radio access network (RAN) is currently captivating the mobile industry. As more mobile operators and governments embrace the desire to diversify the network equipment supplier ecosystem, the debate continues on the merits and measures needed to accelerate this shift.

But what are the drivers and uncertainties in this path towards disaggregation and diversification of RAN infrastructure?

As the build out of 5G connectivity gathers pace, mobile operators are looking to transform their networks in highly significant ways. Motivated by the convergence of technical, commercial and political factors, many mobile operators are embracing new architectures based on the network design principles of virtualisation, cloud computing, open interfaces and network automation.

But let’s be clear, open interfaces and virtualisation are not new technology principles by themselves. However, the application of these principles, with the disaggregation of the RAN infrastructure into interoperable elements and hardware and software, is creating alternative ways to build mobile networks.

Momentum is growing as the vendor ecosystem ramps up the product portfolio and operators commit to more trials and deployments. Highlighting the growing demand for more flexibility, four European operators recently pledged to work together. Their aim is to help drive the development of the disaggregated RAN ecosystem and to commence operation as soon as solutions become mature enough.

Diversification of the mobile RAN supply chain is also driving governments to take notice. Most recently, the UK government, following its decision to remove High Risk Vendors from UK networks, set its supply chain diversification objectives as supporting existing suppliers, attracting new suppliers and accelerating open interface solutions. It has announced funding for testbeds, trials and interoperability testing of open interface solutions.

Open and virtualised RANs are expected to deliver both technical and economic benefits, increasing the flexibility and diversity of the network equipment and software ecosystem and spurring innovation. By reducing the cost, open and virtualised RAN will also help to optimise the almost trillion-dollar global operator investment needed to achieve connectivity targets.

However, as is often the case with the early phase of innovative solutions, a number of challenges will need to be overcome to enable mass deployment of these technology principles.

In our recently published paper, Open and Virtualised Radio Access Networks, An Explanatory Guide for Policymakers, we outline some of the challenges, including the security of networks, industry readiness and cost effectiveness. Whilst the mobile industry is undertaking a number of initiatives to address, there is a recognition that accelerated measures are needed to ensure equipment interoperability, security and reliability, as well as sufficient systems integration capabilities and skills.

Mobile infrastructure is a competitive differentiator, and each operator will make its own network design and configuration choices to align with different business strategies and demand scenarios. However, policy has a role in this evolution, creating an enabling environment that will support the deployment of new RAN infrastructure. Our paper also identifies a number of ways in which policymakers can support the transition to mix-and-match RAN infrastructure including:

· Funding research and development;

· Providing security assurance and certification;

· Promoting and recognising specifications that enable interoperability; and,

· Accelerating 5G network deployment.

Open and virtualised RAN is at its early stages of deployment. To date, the adoption of open and virtualised RAN has been driven through industry cooperation in international fora and standardisation. Industry-led actions, complemented by policy enablers, will help to answer the unknowns and accelerate this trend towards mix-and-match RAN infrastructure. Public Policy