Contextaware service composition in pervasive computing environments , A major challenge in pervasive computing environments is to provide users with complex, contextsensitive applications, dynamically composed from networked services. In this paper, we present an approach to the dynamic, contextaware composition of services to perform user tasks, i.e., software applications abstractly described on the useru0027s handheld device. Both networked services and user tasks are modeled as semantic Web services in OWLS extended with context information. The distinctive feature of our solution is the ability to compose Web services that expose complex behaviors (conversations) to realize a user task that itself has a complex behavior. Furthermore, the contextrelated requirements of the task are met by aggregating the contextsensitive behaviors of the individual services.

Coordination of Ubiquitous Devices in Pervasive Environments: A Proposal Based on WSCDL Context: Ubiquitous devices are usual in our daily lives. We are permanently interacting with those devices, and with the services they offer. Problem: Ubiquitous devices do not provide services in isolation; they cooperate with other devices. Cooperation mechanisms are primarily proprietary. The few proposals from academy have hardly achieved an impact in practice. This contrasts with web services in the Internet environment, which have standardized mechanisms for the composition of services. Aim: We explore the application of Service Oriented Architecture (SOA) specifications and standards for the coordination of ubiquitous devices in pervasive environments. Methodology: We apply Design Science. This methodology allows the iterative construction and evaluation of artifacts. Results: A coordination framework based on WSCDL has been built for ubiquitous devices, along with a proof of concept that demonstrates that the framework works properly in a laboratory environment. The transition to real environments looks straightforward.