Measurement and Development Cost Implications of Component Commonality in Software Product Line Engineering

Abstract

Nowadays, software firms are applying the Software Product Line Engineering (SPLE) approach for its concepts of commonality and variability to provide product variety in a cost-effective manner. Yet, the effect of different amounts of component commonality on the perceived benefits from adopting SPLE is not well understood. Measuring commonality marks the starting point of precise analysis and better understanding of this relationship. In this paper, analytical tools developed in manufacturing are analyzed and adopted (i.e. Commonality Indices (CI)) in order to measure the commonality in SPLE. We used a case study of a Door Lock Control System (DLCS) for evaluating different levels of component commonality. To map the component commonality to the resulting development cost, linear regression is used to assess the relationship between the various commonality indices and the resulting development cost. This study suggests that reusing commonality indices from the manufacturing domain to assess the commonality of products in software product lines is sensible. The linear regression analysis shows that the relationship between those indices and development cost is verifiable, with high R2 value ranges between 0.81 and 0.95, and significant, at the 0.025 ~ 0.005 level.