Considering service-based processes, the problem of determining the service candidates that fit best to a user’s target weights and requirements regarding certain non-functional properties is known as QoS-aware service selection problem. Referring to multi-user processes, this requires taking into account several users with their individual goals. In this regard, users could also have preferences in the sense of user-defined requests referring to other users, so-called Inter-User-Requests (IUR). Such IUR result in dependencies among different users’ service compositions that have to be taken into account when selecting services. However, due to the dynamic environment in which services are used certain events –like the failure of a service – may occur during process execution that require service re-selection atruntime. In this work, we provide such a service re-selection approach in terms of an optimization modelthat considers multiple users and dependencies resulting from IUR. Moreover, for the temporal coordination of the users – necessary for time-dependent IUR – we further propose a continuous time conceptand integrate that in our model. Supported by our evaluation, we feel confident that this approach canserve as a first step for a comprehensive multi-user service re-selection approach where dependenciesamong users exist.

First Page


Last Page