Coordinating Large Distributed Process Structures

Representing a business process as interacting small processes has become feasible with data-centric business process management paradigms. These small processes have relations and, thereby, form a relational process structure. The interactions of processes within this relational process structure must be coordinated to arrive at a meaningful overall business goal. However, relational process structures may become arbitrarily large and, with cloud technology, they may additionally be distributed over multiple nodes. Coordination processes have been proposed to coordinate relational process structures, where processes have one-to-many and many-to-many relations at run-time. This paper shows how multiple coordination processes can be used in a decentralized fashion to coordinate large, distributed process structures. The main challenge is to effectively realize the coordination responsibility of each coordination process. Key components of the solution are the subsidiary principle and the hierarchy of the relational process structure. Moreover, from these key components and the technical properties of coordination processes, an implementation based on microservices was developed, which allows fast and concurrent enactment of multiple, decentralized coordination processes in large, distributed process structures.