One of the defining features of 5G was supposed to be its disaggregated, virtualized architecture. This was going to transform the economics of deployment by breaking apart basebands and radio heads, and virtualizing some or all of the baseband functions in software, resulting in a more flexible, multivendor, cost-effective and scalable RAN.
In reality, the complexity, and immature standards, for virtualized RANs have delayed progress and most first-phased 5G networks are conventional in architecture. In particular, operators face complex choices in how they make the splits between virtual and physical functions, and between cell site and centralized locations. Many of these choices will depend on the primary 5G use cases to be supported, yet most operators have not fully worked these out yet.
In some ways, these challenges are even higher in small cells than in the macro network because of the sheer number and variety of elements involved. Yet progress towards fully virtualized and disaggregated access networks, managed by software-defined networking (SDN) in the control plane, has been more rapid in the small cell layer. This is partly because most small cell networks are greenfield, and there is not the same risk that come with migrating a well-established and business-critical macro RAN.
At this year’s Small Cells World Summit, to be held in London on May 21-22, operators and vendors will share the experience they have gained from early, 4G-based virtualization initiatives, which will provide invaluable help for those planning 5G densification.
Small Cell Forum’s work on open interfaces such as FAPI and nFAPI has had an important impact on the early deployability of open, disaggregated systems at chip and network level. The latest steps in this crucial work will be outlined at the event, including the path to 5G FAPI, and the work with open source bodies to get these technologies out to the widest range of stakeholders.
But while several suppliers now offer centralized, disaggregated small cell platforms, especially for indoor systems, there are many further challenges to be addressed before a full end-to-end, software-driven 5G architecture is ready to roll out.
These will be addressed in a major, in-depth session entitled ‘Disaggregated architectures, virtualization and open source’ on Wednesday May 22. This will examine technical and commercial considerations and provide essential insights for those grappling with their own decisions about the best architecture for a dense 4G or 5G network.
For instance, speakers and a panel of experts will debate which is the best functional split for particular business cases, and indeed, whether split architectures are essential to virtualization at all. The benefits of disaggregation, whether for performance or to drive an open cost-effective ecosystem, will be discussed, along with the different requirements of indoor and outdoor environments.
For disaggregated RAN, new fronthaul and backhaul technologies will be essential to drive the best performance and these will also be under review as they affect the vision for a full 5G transport architecture.
Executives from two major operators, the UK’s BT and India’s Reliance Jio, will discuss their architectural choices and the road to 5G, while there will also be inputs from the Telecom Infra Project, which is driving open xHaul and RAN platforms, as well as providers of silicon, optical and wireless transport, and NFV/SDN solutions.
To get fully up-to-date with this complex and essential topic, and learn from some of the earliest adopters, make sure you secure a place at this year’s SCWS here.