Abstract

An emerging trend in software application design is to provide mechanisms to let end-users customize the look-and-feel of their usage experience and even extend behaviour in order to satisfy personalized requirements. Telecommunication service providers, now offered open access to core networks with enhanced multimedia capabilities, are today in demand of solutions to capitalize on the next-generation infrastructure and the market trend in relation to Internet Telephony service creation. Current proposals to meet the demand have the disadvantage of being inflexible or not feasible for the near-term. In this thesis, we describe our approach for a flexible framework to enable service composition and personalization. Moreover, we demonstrate how our approach may be applied today. Our framework lets end-users, or third-parties acting on their behalf, create added-value by composing existing services in new ways. As a consequence of empowering the end-user with an unprecedented level of control over their services, we must ensure that personalized service configurations can and will behave as expected, and not in detriment to the overall system. Therefore, we have also developed a mechanism to guarantee the absence of conflicting service behaviour, to a certain degree. In providing the guarantee we have dealt with a fundamental problem in Service Engineering, namely, Feature Interaction. Our solution is based on our enhancement of SERL, a language and framework for managing the triggering and execution of services. We have defined language extensions to let experts impose service composition constraints. Moreover, we have designed algorithms for validating user-defined service configurations against constraints. Finally, we have designed and implemented a proof of concept prototype in a Parlay/OSA context which virtually composes services at runtime according to the configurations. In two Case Studies, we demonstrate the approach and the added-value created.