Toward synchronization between decentralized orchestrations of composite web services

Web service paradigm and related technologies have provided favorable means for the realization of collaborative business processes. From both conceptual and implementation points of view, the business processes are based on a centralized management approach. Nevertheless, it is very well known that the enterprise-wide process management where processes may span multiple organizational units requires particular considerations on scalability, heterogeneity, availability and privacy issues, that in turn, require particular consideration on decentralization. In a previous work, we have described a flexible methodology for splitting a centralized process specification into a form that is amenable to a distributed execution. The approach is based on the computation of very basic dependencies between process elements. In this paper, we extend this approach to support advanced patterns such as loops, multiple instances and discriminator, and incorporate the necessary synchronization between the different processing entities. We also detail our interconnection mechanism and explain how to handle control and data dependencies between activities of the different partitions through asynchronous message exchanges. The proposed methodology preserves semantics of the centralized process with a peer-to peer interactions among the derived decentralized processes.