Handling Cross-Cutting Concerns in Subject-Oriented Modeling: Exploration of Capabilities and an Aspect-Oriented Enrichment

Subject-oriented modeling has recently found increased application for the modeling of processes in Cyber-Physical Systems (CPS). While models are generally used as a means of dealing with the complexity of such systems, modeling languages are challenged by various cross-cutting concerns that are inherently difficult to depict in an efficient manner. Common examples include regular logging mechanisms, authentication procedures, and the like. If not appropriately supported by the used language, modeling such concerns can result in duplicated model elements that are scattered across the same or different models. They furthermore become tangled with the core functionality needed to realize a business case. This negatively impacts qualities such as model understandability, reusability, maintainability, and evolution. Aspect-oriented programming and modeling concepts have been applied in different contexts to address such issues. In this contribution, we examine subject-oriented modeling with regard to its capabilities for supporting modularity and separation of concerns using the running example of a logistics CPS. Certain limitations are present that could be addressed by an aspect-oriented enrichment. We outline an initial proposal and discuss related considerations and challenges.