Modeling and Controlling Dynamic Service Compositions

Service-oriented computing paradigms have considerably enhanced support for dynamic in modern computing environments by providing loosely coupled interactions between components. The key attainment is the ability to perform a late binding of service compositions, i.e., an allocation of actual services to service place holders during run-time. However, this attainment is limited to the binding of services and cannot operate on the service composition plans itself. Moreover, many service composition representations do not consider the realtime behavior of single services, failing to address a key need of service compositions within dynamic environments that are characterized by a high node mobility. Within this paper, we introduce a service composition model based on a bipartite graph representation that enables the rapid modification of already existing service composition plans. Here, the workflow within a service composition is modeled with a timed automaton while a labeled digraph ensures the correct flow of data between the single services.