The new computing environment enabled by advances in service oriented
arc- tectures, mashups, and cloud computing will consist of service
spaces comprising data, applications, infrastructure resources
distributed over the Web. This envir- ment embraces a holistic paradigm
in which users, services, and resources establish on-demand
interactions, possibly in real-time, to realise useful experiences. Such
interactions obtain relevant services that are targeted to the time and
place of the user requesting the service and to the device used to
access it. The bene't of such environment originates from the added
value generated by the possible interactions in a large scale rather
than by the capabilities of its individual components se- rately. This
offers tremendous automation opportunities in a variety of application
domains including execution of forecasting, of?ce tasks, travel support,
intelligent information gathering and analysis, environment monitoring,
healthcare, e-business, community based systems, e-science and
e-government. A key feature of this environment is the ability to
dynamically compose services to realise user tasks. While recent
advances in service discovery, composition and Semantic Web technologies
contribute necessary ?rst steps to facilitate this task, the bene?ts of
composition are still limited to take advantages of large-scale ubiq-
tous environments. The main stream composition techniques and
technologies rely on human understanding and manual programming to
compose and aggregate s- vices. Recent advances improve composition by
leveraging search technologies and ?ow-based composition languages as in
mashups and process-centric service c- position.
