Gluing Grids and Clouds Together: A Service-Oriented Approach

Scientific communities are actively developing services to exploit the capabilities of service-oriented distributed systems. This exploitation requires services to be specified and developed for a range of activities such as querying, management and scheduling of workflows, image handling, provenance capture and management, amongst other activities. Most of these services are designed and developed for a particular community of scientific users. A key issue here is that the constraints imposed by architectures, interfaces or platforms can restrict or even prohibit the free interchange of services between disparate scientific communities who have a shared need for a particular service. Using the notion of "Platform as a Service" (PaaS), we propose an architectural approach that addresses these limitations so that that users can make use of a wider range of services without being concerned about the development of cross-platform middleware, wrappers or any need for bespoke applications in order to cross the boundaries between differing communities. The proposed architecture shields heterogeneous Grid and Cloud infrastructural detail with a brokering environment, thus enabling users to concentrate on the specification of higher level services that are more relevant to the intended application.