Workflow-based Grid applications

Standardization, usability, and business models are the main success factors for next generation Grid computing systems. This paper focuses on standards and usability within the context of the Fraunhofer Resource Grid that implements a simple, Petri net-based graph model for orchestrating Grid Services and legacy command line applications on OGSI-compatible middleware. The design and prototype implementation of a Grid workflow management system is presented, including a set of description languages required for orchestrating abstract workflows and for mapping them onto real Grid infrastructure, as well as a workflow enactment service that executes loosely coupled Grid jobs on the Grid.