Policy driven adaptation of context-aware services with preferences supporting

Ubiquitous computing has revolutionized the way we use computing. The widespread of wearable devices and the seamless connectivity between them have transcended the traditional computing era to the pervasive computing and enable new opportunities for a user to perform his/her operation all the time and everywhere. These new environments are characterized by large quantity of heterogeneous services and context-aware applications that dynamically join and leave the network. Such environment will constitute a large-scale internetworking infrastructure and likely to provide a new level of openness and dynamics. For achieving its goal, ubiquitous computing needs the context data brought by the seamlessly connected devices either mobile handset or embedded in the surrounding physical environment and imperceptible to a user. Indeed, context and context-awareness provide computing spaces with the capability to usefully adapt the services they provide. We present our mechanism of adaptation of services by a policy-driven, context-aware manner. The adaptation is based on enumerating the different policies of a service object. As the execution environment, user context and preferences change, the service object will be adapted to use different behaviors, driven by user preferences. The adaptation process is able to capture and to process context-dependent preferences and qualitative uncertainty labels which are used to determine which set of preferences should be considered in a given context. To demonstrate this mechanism we will provide an example scenario and evaluate our solution.