Enabling Efficient Service Distribution using Process Model Transformations

The challenge of service distribution has been considered in the fields of cross-organizational interoperability, grid computing and task delegation but little addressed for cross-zone application deployment in Cloud Computing. This paper proposes a process model transformation technique based on activity aggregation to efficiently distribute services for the Web of Data between various Cloud availability zones. The authors propose a workflow decomposition method based on SPQR fragments and the definition of an efficient service distribution algorithm according to a defined cost model. This cost model considers not only the transmission of information between activities for data and control scopes but also the cost of activity execution in different regions. Finally the authors validate their method by providing a tool that introduces the distribution information into the workflow, applying their distribution algorithm in a use case and describing the transformation process to distributed BPEL code that can be easily deployed to back-end instances.