Experiences of sampling-based approaches for estimating QoS parameters in the Web Service composition problem
Eduardo Blanco, Yudith Cardinale, María-Esther Vidal · International Journal of Web and Grid Services · 2012
QoS parameters can be used to characterise services or their compositions according to non-functional criteria. We propose samplingbased techniques to accurately estimate QoS values that will be used in a hybrid composer named PT-SAM, to identify the compositions that best meet a user request. PT-SAM adapts a Petri-Net unfolding and uses a utility function defined on the QoS estimates, to guide the composer. We report on the quality of the estimates and the performance of the composer. Our experiments show that solutions generated by PT-SAM are close to the optimal solutions while the composer can scale to large search spaces.