Security in Open Model Software With Hardware Virtualization - The Railway Control System Perspective

Using the openETCS initiative as a starting point, this paper describes how open software can be applied in combination with platform-specific, potentially closed source extensions, in the development, verification, validation and certification of safety-critical railway control systems. This paper analyses the safety and security threats presented by this approach and discuss conventional operating system partitioning mechanisms, as well as virtualisation methods with respect to their potential to overcome these problems. Furthermore, this paper advocates a shift from open source to open models, in order to increase the development efficiency of combined open and proprietary solutions.