A Formal Model and Analysis of Feature Degradation in Fault-Tolerant Systems

摘要: Fault-tolerant systems have to react on errors resulting from faults properly avoid error propagation and finally a harmful failure of the entire system. Beside detection failing system elements, also actions handle failures are essential cover safety requirements. Actions reach enabling fail-silent, fail-safe or fail-operational behavior hybrids this in mixed-critical design. Graceful degradation may be applied when resources become insufficient, reducing set provided functional features. In paper we address mixed critical systems, which partially comprise We consider degradations features scenarios. describe formal model that contains i.a. system, possible feature degradations, software components realize these features, as well deployment execution units. calculate valid deployments units analyze them according level graceful level, consequence components. show an example automotive domain illustrate our approach.