Software-based Networking in Railway Systems

Railway networking systems are critical infrastructures that must support fast, reliable and low delay communications. Technologies still used in those infrastructures---such as GSM-R, evolving into LTE-R are becoming more complex, yet more flexible, and evolving to "software defined" architectures. The technologies presented and explored in this work are expected to change the future of these types of critical systems. The main goal of this work is to study the key benefits of using the SDN model to control the next generation railways networking infrastructures. The safety, security and correctness properties of SDN controllers in high availability railway networks will be analyzed, for compliance with the European Rail Traffic Management System (ERTMS)/European Train Control System (ETCS) specifications, and in the context of a real project being deployed in a Portuguese Railway by Thales Portugal. From the analysis of the project requirements and the selected network equipment, it was possible to evaluate and propose adequate methods to automatically derive network re-configuration strategies, namely in case of failure events---e.g., preventing packet loss affecting vital railway traffic signaling procedures---in order to reduce field intervention and complexity in those infrastructures.