Software application design based on architecture, reliability and cost

In this paper we present an optimization framework based on an evolutionary algorithm to design a modular software application taking into account its architecture, reliability and cost. The specific design problem that we address is the reliability maximization of a software application subject to a specified cost constraint. Evolutionary algorithm (EA) is used as an optimization technique because of the discontinuous search space, usually nonlinear but monotonic relation between cost and reliability of individual modules comprising the software application and complex software architectures giving rise to nonlinear dependencies between individual module reliabilities and the overall application reliability. We demonstrate how the EA can be effectively and efficiently to design a software application using three case studies.