Tackling the provenance challenge one layer at a time

VisTrails is a new workflow and provenance management system that provides support for scientific data exploration and visualization. Whereas workflows have been traditionally used to automate repetitive tasks, for applications that are exploratory in nature, change is the norm. VisTrails uses a new change-based provenance mechanism, which was designed to handle rapidly evolving workflows. It uniformly and automatically captures provenance information for data products and for the evolution of the workflows used to generate these products. In this paper, we describe how the VisTrails provenance data are organized in layers and present a first approach for querying this data that we developed to tackle the Provenance Challenge queries.