Federating heterogeneous event services

As event-based middleware is currently being applied for application component integration in a range of application areas, a variety of event services have been proposed to address different application requirements. The emergence of ubiquitous computing systems has given rise to application integration across multiple areas and as a result, has led to systems comprising several, independently operating event services. Even though event services are based on the same communication pattern, application component integration across heterogeneous services is typically prevented by the constraints imposed by their respective event models. This paper presents the design and implementation of the Federated Event Service (FES). The FES enables heterogeneous event services to cooperate and to operate as a single logical service. It therefore facilitates building event-based systems in which the application requirements cannot be met by a single event service.