Modeling Variability from Requirements to Runtime

In software product line (SPL) engineering, a software configuration can be obtained through a valid selection of features represented in a feature model (FM). With a strong separation between requirements and reusable components and a deep impact of high level choices on technical parts, determining and configuring an well-adapted software configuration is a long, cumbersome and error-prone activity. This paper presents a modeling process in which variability sources are separated in different FMs and inter-related by propositional constraints while consistency checking and propagation of variability choices are automated. We show how the variability requirements can be expressed and then refined at design time so that the set of valid software configurations to be considered at run time may be highly reduced. Software tools support the approach and some experimentations on a video surveillance SPL are also reported.