openETCS: From Open Source to Open Proofs for the European Train Control System

• Conference
• Advanced

The “European Train Control System” (ETCS), is going to replace national legacy signaling and train control command systems across Europe and is expected to eliminate national barriers for railway transit. This goes along with a significant increase of complexity for safety critical onboard functions. Such functions are implemented in “embedded control systems” by software. Electronic hardware is continuously becoming cheaper but more powerful at the same time; while increasing complexity of the software has caused cost figures to go up for R&D, homologation, as well as system maintenance. Railway operators are not only questioning the economics but are also concerned whether such complex software systems will provide the same level of safety and security compared with less complex, mature, and service proven legacy systems. “openETCS” is based on a concept, called "open proofs", which requires the entire implementation, automatically-verifiable proofs, and all needed tools for use and modification to be licensed as Free/ Libre/ Open Source Software (FLOSS). Both, economical and technical problems are addressed equally by the use of state-of-the-art formal methods, cost sharing effects and broadening peer-to-peer review basis, taking into account recent technical standards (e.g. EN50128:2011) for software life cycle management.