Modeling PLA variation of privacy-enhancing personalized systems

Privacy-enhancing personalized (PEP) systems address individual users' privacy preferences as well as privacy laws and regulations. Building such systems entails modeling two different domains: (a) privacy constraints as mandated by law, voluntary self-regulation, or users' individual privacy preferences, and modeled by legal professionals, and (b) software architectures as dictated by available software components and modeled by software architects. Both can evolve independently, e.g., as new laws go into effect or new components become available. In prior work, we proposed modeling PEP systems using a product line architecture (PLA). However, with an extensional PLA, these domain models became strongly entangled making it difficult to modify one without inadvertently affecting the other. This paper evaluates an approach towards modeling both domains within an intensional PLA. We find evidence that this results in a clearer separation between the two domain models, making each easier to evolve and maintain.