A control system for managing the flexibility in BPMN models of cloud service workflows

In this paper, we present a real time interactive system for running flexible workflow applications. This system facilitates the execution of these applications in terms of time execution complexity as it is based on flexibility mechanism. These workflows are built on an abstract level, through BPMN models using flexibility patterns. We define two flexibility patterns based on BPMN (Business Process Model Notation) that deals with changes of resource requirements for workflows. The provided models specify the functional view of workflows, whereas, their behavioral view is described using state-chart diagrams. A state-chart diagram represents the model specifying our real time system which controls the execution of workflow applications by making decisions on the use of flexibility actions. This execution is supported by the BPEL4WS engine that we have amended to execute flexible workflows and to be controlled by our real time system. Finally, we present some results of evaluations of our system.