A metrics-based decision support tool for software module interfacing technique selection to lower maintenance cost

The Interfacing Techniques Comparison Graph visually compares applications in terms of attributes that relate to maintenance cost. Applications that have both lower coupling and lower complexity lie closer to the origin of the graph and exhibit lower maintenance cost than those that do not. The study supports the idea that compositional techniques are important for achieving these improved metrics. The graph can be used in three ways. First it serves as a decision support tool for managers to determine whether expected maintenance savings compensate for the additional training, effort and time needed to support compositional development. Second, it functions as a decision support tool for designers and coders as they determine, for each module interface, whether to use coupled techniques or composition. The graph can help identify those situations in which the long term cost gain justifies the extra time needed for compositional design. Third, it can serve as a maintenance cost estimation tool. The study found a close correlation between predicted and actual maintenance effort.