Components, Safety Interfaces, and Compositional Analysis
2007 (English)Licentiate thesis, monograph (Other academic)
Component-based software development has emerged as a promising approach for developing complex software systems by composing smaller independently developed components into larger component assemblies. This approach offers means to increase software reuse, achieve higher flexibility and shorter time-to-market by the use of off-the-shelf components (COTS). However, the use of COTS in safety-critical system is highly unexplored.
This thesis addresses the problems appearing in component-based development of safety-critical systems. We aim at efficient reasoning about safety at system level while adding or replacing components. For safety-related reasoning it does not suffice to consider functioning components in their intended environments but also the behaviour of components in presence of single or multiple faults. Our contribution is a formal component model that includes the notion of a safety interface. It describes how the component behaves with respect to violation of a given system-level property in presence of faults in its environment. This approach also provides a link between formal analysis of components in safety-critical systems and the traditional engineering processes supported by model-based development.
We also present an algorithm for deriving safety interfaces given a particular safety property and fault modes for the component. The safety interface is then used in a method proposed for compositional reasoning about component assemblies. Instead of reasoning about the effect of faults on the composed system, we suggest analysis of fault tolerance through pair wise analysis based on safety interfaces.
The framework is demonstrated as a proof-of-concept in two case studies; a hydraulic system from the aerospace industry and an adaptive cruise controller from the automotive industry. The case studies have shown that a more efficient system-level safety analysis can be performed using the safety interfaces.
Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press , 2007. , 136 p.
Linköping Studies in Science and Technology. Thesis, ISSN 0280-7971 ; 1317
Component-based system development, safety-critical systems, safety interfaces, compositional analysis, modelbased development
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-57490Local ID: LiU-Tek-Lic-2007:26ISBN: 978-91-85831-66-1OAI: oai:DiVA.org:liu-57490DiVA: diva2:325946
2007-06-07, Visionen, hus B, Campus Valla, Linköpings universitet, Linköping, 10:15
Nadjm-Tehrani, Simin, Professor