Joint optimization of ICD and reliability for component selection incorporating "build-or-buy" strategy for component based modular software system under fuzzy environment

Abstract

Design phase of software development life cycle for designing software with high quality attributes which meets functional requirements is quite a tedious task. In real life the developers can only make ambiguous estimates on the available resources and their aspirations bringing uncertainty (fuzziness) in the problem formulation. In such situations, crisp optimization technique may not serve the purpose to quantify desired parameters. In this paper we have formulated a fuzzy optimization framework which supports build or buy decision strategy i.e., whether to buy software components or to build them in-house or a combination is more beneficial. In this paper, intra-modular coupling density and reliability are jointly optimized under permissible budget and delivery time constraints along with an ICD restriction applied at module level. Redundancy is allowed for the selection procedure for fulfilling each functional requirement. An optimization model for optimal selection of components has been proposed and is illustrated with numerical example.