A sufficient and necessary temporal violation handling point selection strategy in cloud workflow

To deliver high QoS (quality of service) for business process participants, workflow temporal verification is conducted to provide satisfactory on-time completion rate of business process in the cloud. Temporal violation handling is the last task in a typical workflow temporal verification framework to deal with detected time delays. However, there are very few existing studies regarding temporal violation handling for cloud business workflows. In this paper, queuing theory is first employed to simulate time features of parallel workflow instances. Then, propagation effect based temporal consistency model for business workflows and temporal consistency model for workflow activities in the same queuing system are presented respectively. Finally, a promising temporal violation handling point selection strategy for cloud business workflows is proposed and proved to satisfy the property of sufficiency and necessity. Compared with other representative strategies, experimental results show that our novel handling point selection strategy can reduce the monitoring and handling cost while maintaining the target on-time completion rate agreed between users and service providers.