Introducing Network Softwarization in Next-Generation Railway Control Systems

The advent of softwarization implies a re-thinking of network design and management that positively impacts on service provisioning and maintenance efficiency. In particular, Software Defined Networking and Network Function Virtualization introduce abstraction techniques that are suitable for an easy and efficient deployment of service chain and for the use of general purpose hardware devices. The introduction of these paradigms in the railway domain is challenging due to its strict service and safety requirements, however it represents a promising approach enabling a disruptive improvement of the management systems and paving the way for next-generation railway control systems.This paper discusses and proposes the adoption of SDN/NFV (Software Defined Networks/Networks Function Virtualization) framework in railway control networks. In particular, some possible promising directions of investigation are drawn considering service orchestration and edge-based NFV services. Furthermore, two different applications are described focusing on SDN and NFV, respectively. An improved SDN failure recovery mechanism is proposed and evaluated showing the improvement in terms of recovery time. Instead, the introduction of configurable orchestration systems aiming to dynamically instantiate required services on Virtual Machines directly in the railway peripheral places by means of edge computing solutions for maintenance operations of peripheral assets is described and discussed.