Towards agent-based modelling and verification of collaborative business processes: An approach centred on interactions and behaviours

This paper presents the process-oriented aspects of a formal and visual agent-based business process modeling language. The language is of use for (networks of) organizations that elect or envisage multi-agent systems for the support of collaborative business processes. The paper argues that the design of a collaborative business process should start with a proper understanding of the work practice of the agents in the business domain under consideration. The language introduces a novel diagram to represent the wide range of (cross-enterprise) business interactions as a hierarchy of role-based interactions (including their ordering relations) in a tree structure. The behaviors owned by the agents playing the roles in the tree are specified in separate process diagrams. A collaborative business process studied in the context of a case study at a Dutch gas transport company is used to exemplify the modeling approach. Explicit (agent-based) process models can and should be verified using formal methods. In the business process community, design-time verification of a process design is considered vital in order to ensure the correctness and termination of a collaborative business process. The proposed modeling approach is enhanced with a design-time verification method. The direction taken in this research is to combine the interaction tree and the associated agent behaviors into a verifiable hierarchical colored Petri net in order to take advantage of its well-defined (execution) semantics and proven (computerized) verification techniques. The verification method presented in this paper consists of three steps: (1) the translation of the agent-based process design to a hierarchical colored Petri net, (2) the identification of process design errors, and (3) the correction and rollback of process design errors to the agent-based model. The translation technique has been implemented in a software tool that outputs the hierarchical colored Petri net in a format that can be loaded in the widely used CPN Tools software package. Verification results are discussed for the case study model.