Optimizing the reliability of component-based n-version approaches

In this paper a component-based approach for implementing n-version software systems is prresented. For each of the system modules, a set of diversely developed module candidates is considered. It is demonstrated that in general such a modular construction offers a potential to considerably increase the reliability of the n-version system. Moreover, we describe an optimization approach to further optimize system reliability by selecting the most adequate candidates while at the same time observing given system constraints. A heuristic search algorithm to find optimal system configurations is sketched. Several modifications of this algorithm are discussed. Simulation results concerning the outcome of these different approaches are presented.