A Formal Framework For Multi-Party Business Protocols (Revision of CentER DP 2008-79)

Enterprise-class information systems based on the principles of Service Oriented Architecture comprise large numbers of long-running, highly dynamic complex end-to-end service interactions, called conversations, based on message exchanges that typically transcend several organizations and span several geographical locations. Conversations in service-based systems can be described using business protocols that are formal notations specifying the timed message exchanges among participants in a conversation from a local point of view (orchestrations) or global (choreographies). In this work we introduce a formal framework based on Deterministic Finite Automata enriched with temporal constraints to describe multi-party business protocols. We also explore the notion of multi-party business protocol soundness and show how it is possible to execute a multi-party protocol consistently in a completely distributed manner and at the same time ensure the progression of the execution (i.e. no “deadlocks”).service oriented architecture;message exchange patterns business protocols;orchestrations;choreographies;soundness

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