Reusable Interaction Protocols for Workflows

With the advent of collaborative business processes that may include different parties, the interaction means between those processes steadily gains more importance. Despite this issue the modeling of message-based interactions is very complex and errorprone due to the inherent properties of asynchronous communication. In order to alleviate this problem several predefined interaction protocols such as contract-net or different auction types have been defined in the context of multi-agent systems. In this paper it is shown how these interaction protocols can be described in a reusable way for BPMN workflows. The underlying idea is to hide the complete message-based complexity of the underlying protocol specification and allow to employ them in a completely domain oriented fashion, i.e. the workflow modeler is only concerned with initiating a specific type of interaction and fetching the results. For this purpose the ideas of agent-based goal-oriented interactions have been simplified and transferred to the workflow modeling area. The usefulness of the approach is exemplified by an example that illustrates how contract-net negotiations can be set-up.