Most workflow management systems (WfMSs) only support the separate and independent execution of business processes. However, processes often need to interact with each other, in order to synchronize the execution of their activities, to exchange process data, to request execution of services, or to notify progresses in process execution. Recent market trends also raise the need for cooperation and interaction between processes executed in different organizations, posing additional challenges. In fact, in order to reduce costs and provide better services, companies are pushed to increase cooperation and to form virtual enterprises, where business processes span across organizational boundaries and are composed of cooperating workflows executed in different organizations. Workflow interaction in a cross-organizational environment is complicated by the heterogeneity of workflow management platforms on top of which workflows are defined and executed and by the different and possibly competing business policies and business goals that drive process execution in each organization. In this paper we propose a model and system that enable interaction between workflows executed in the same or in different organizations. We extend traditional workflow models by allowing workflows to publish and subscribe to events, and by enabling the definition of points in the process execution where events should be sent or received. Event notifications are managed by a suitable event service that is capable of filtering and correlating events, and of dispatching them to the appropriate target workflow instances. The extended model can be easily mapped onto any workflow model, since event specific constructs can be specified by means of ordinary workflow activities, for which we provide the implementation. In addition, the event service is easily portable to different platforms, and does not require integration with the WfMS that supports the cooperating workflows. Therefore, the proposed approach is applicable in virtually any environment and is independent on the specific platform adopted.
ASJC Scopus subject areas
- Earth and Planetary Sciences(all)