Safety and Availability

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The objective addressed in this project is, how safety and availability properties can be ensured in a system which undergoes changes of multiple components, potentially concurrently, throughout its lifetime. The design of safety critical systems is regulated by safety standards, which currently do not allow adaption of the systems without recertification. If adaptaions are unpredictable at design-time, as they may be context-driven, user-driven or the result of component failure, current safety standards require overprovisioning and sufficient isolation. In the context of systems as addressed in CCC, such static design-time overprovisioning is not acceptable. In this project we plan to develop a novel design process along with methods, that allow to partition the assurance of safety and availability properties into a lab-based and an in-field part to be executed after deployment. The investigations in the first project phase made clear that automating essential steps of failure analysis is key to reach this goal. A model and a corresponding dependency analysis were developed as a basis. They capture and help to determining the variety of influences in complex multilayer employing specialized analysis methods for quantification. While the fundamental approach was developed in project phase 1, the second phase shall be focused on concrete analysis detecting threads for data integrity, determining timing interference and quantifying reliability and availability. The results shall be evaluated given the requirements of safety standards in automotive electronics and avionics. An important goal is the validation of sufficient independence under various effects as required in safety standards. This approach shall, then, be used to validate the MCC cooperation as developed in other CCC projects. Finally, dependency analysis shall be employed to support simple synthesis mechanisms improving functional safety in integration. A larger work package addresses the increasing of availability using reconfigurable hardware components. The results shall be used to establish a situation-aware availability management for systems using the CCC architecture and methods. The mechanisms developed here are integrated into the overarching MCC Middleware, which performs the composition and synthesis based on a contract-description of the applications and primitives.