Probabilistic prediction of the QoS of service orchestrations: A truly compositional approach

The ability to a priori predict the QoS of a service orchestration is of pivotal importance for both the design of service compositions and the definition of their SLAs. QoS prediction is challenging because the results of service invocations is not known a priori. In this paper we present an algorithm to probabilistically predict the QoS of a WS-BPEL service orchestration. Our algorithm employs Monte Carlo simulations and it improves previous approaches by coping with complex dependency structures, unbound loops, fault handling, and unresponded service invocations.