Network sharing and 5G in Europe: The potential benefits of using SDN or NFV

The sharing of fixed and especially of mobile networks is needed to address a range of current or emerging European policy requirements. At the same time, 5G networks are expected to address a range of different use cases, many of which have needs that differ greatly from one another (e.g. not only mobile broadband, but also automotive and Internet of Things (IoT)). To make things even more complex, some of these needs vary dynamically over time. Software Defined Networks (SDN) and Network Function Virtualisation (NFV) are two distinct but possibly mutually complementary technologies that might be used, either alone or together, to achieve greater flexibility as to how communication networks are used. The implementation of dynamically configurable networks, however, requires a redefinition of the major hardware and software modules that comprise the networks, the functions performed by each of these modules, their interfaces, and the associated protocols that allow the modules to communicate with each other. To what extent might the use of SDN and/or NFV technology be used to address these varying requirements within a common network? What benefits might be expected, and what costs? What practical, technological, economic, and regulatory policy implications might flow from the use of SDN and/or NFV in this way, and what are the interactions among these different dimensions? Our assessment suggests that any application of SDN and/or NFV to these challenges would raise concerns that would need to be addressed. Challenges of shared management, of information sharing among competitors, and of the maintenance of privacy (with implications for security) between multiple users of the network can be readily addressed, in our view. It is the resource management requirements that give us pause. We believe that the industry is many years away from implementing offering solid, commercially available, multi-vendor platforms that offer reliable solutions to the challenges of resource management in a shared SDN/NFV environment. If intelligently addressed, these resource management challenges might ultimately be viewed not just as a threat, but also as an opportunity. Analogous resource management challenges are already visible in existing non-SDN/NFV sharing scenarios. SDN/NFV potentially enables solutions that are more flexible, more highly automated, and less expensive to implement and to operate.