Scientific computing has entered a new era of scale and sharing with the arrival of cyberinfrastructure for computational experimentation. A key emerging concept is scientific workflows, which provide a declarative representation of scientific applications as complex compositions of software components and the dataflow among them. Workflow systems manage their execution in distributed resources, track provenance of analysis products, and enable rapid reproducibility of results. In current cyberinfrastructure, there are well-understood mechanisms for sharing data, instruments, and computing resources. This is not the case for sharing workflows, though there is an emerging movement for sharing analysis processes in the scientific community.
This project explores computational mechanisms for sharing workflows as a key missing element of cyberinfrastructure for scientific research, with three major research foci: (1) Elicitation of new requirements that workflow sharing poses over current techniques to share software tools and libraries; (2) Understanding how shared workflow catalogs should be designed, as the existing data catalogs are a successful model, and software components require different representations and access functions; and (3) Studying what sharing paradigms might be appropriate for scientific communities.
Expected results from this work include: use cases for workflow sharing and reuse that motivate this research area, a comparison between software reuse and workflow reuse requirements, a specification of a workflow catalog defining expected functions and services, and an investigation of social issues that arise in building this new kind of shared resource in scientific communities. Results are available at the project Web site (http://workflow-sharing.isi.edu).
