SIL4 Cloud - a novel IT platform architecture for safety-relevant railway applications
With digitalization, a multitude of new technologies will be introduced to the railway system. These will place high demands on IT platforms in regards to reliability, scalability, performance and strict safety requirements. As part of the Digitale Schiene Deutschland sector initiative, DB Netz AG, Thales, SYSGO, Fraunhofer IESE, University of Rostock and ESE, have taken a first important step in this direction and have developed the basic architecture of a "SIL 4 Cloud".
A SIL4 Cloud is a certifiable IT platform in private cloud environments, which will host safety-critical railway applications. According to CENELEC functional safety norms, SIL4 (Safety Integrity Level 4) represents the highest level of safety and reliability in the railway system. In the last months, Thales together with DB Netz AG and the aforementioned partners analysed requirements and researched how to create such a platform architecture for private SIL4 Cloud environments. The overall findings have been captured and published in a detailed report [here]. The report comprises an overview of the system-under-consideration, its generic architecture and potential implementation proposals based on two different solution approaches. One important design paradigm is that the SIL4 Cloud architecture must provide a clear and standardised separation of application, runtime environment and hardware, no matter which specific solution approach is used.
Digital Rail can only be successful with backing in and from Europe. New digital technologies that enter the rail system have to take the European perspective into account from the word go. This also in order to create, for example, an attractively large market for manufacturers within and outside the rail sector. Therefore the research project considered the preliminary work on the generic "Safe Computing Platform" of the European railway initiatives "Reference CCS Architecture" (RCA) and "Open CCS Onboard Reference Architecture" (OCORA), but focused on trackside computing platforms and went significantly beyond the work in RCA and OCORA. It also covered, for example, key highlights on cyber security, modern communication protocols and homologation aspects. The report also describes how the platform approaches of the individual partners meet the RCA/OCORA High-level Objectives.
The report shows that the envisioned SIL4 Cloud approach is generally feasible, although key challenges need to be mastered and important architectural decisions have to be taken.
Thales would like to thank all partners for the excellent and valuable cooperation and for wide range of contributions and perspectives on this collaboration.
Click here to access the detailed research report of the SIL4 Cloud project.