Selecting Optimal Maintenance Plans Based on Cost/Reliability Tradeoffs for Software Subject to Structural and Behavioral Changes

Software maintenance is assuming ever more a crucial role in the lifecycle due to the high variability of software requirements and environment. New development paradigms are being defined to support the numerous decisions that have to be taken after the software deployment. On the basis of the increasing request of software quality, nonfunctional attributes should enter in the decisional process to avoid changes that compromise the software quality. In this paper we define an optimization model that drives the choice of a maintenance plan (i.e. a set of maintenance actions to be taken) in correspondence of a certain change scenario. A change scenario is a set of new requirements that induce changes in the structural and behavioral architecture of the software system. The solution of such model, as shown in this paper on a mobile application, provides the set of actions that minimize the maintenance cost while guaranteeing a certain level of software reliability. We also show how this instrument can be used to perform a sensitivity analysis of maintenance plans vs cost/reliability tradeoff.