ANDROMEDA:: Building e-science data integration tools

This paper presents ANDROMEDA (Astronomical Data Resources Mediation), an XML-based data mediation system that enables transparent access to astronomical data sources. Transparent access is achieved by a global view that expresses the requirements of a community of users (i.e., astronomers) and data integration mechanisms adapted to astronomical data characteristics. Instead of providing an ad hoc mediator, ANDROMEDA can be configured for giving access to different data sources according to user requirements (data types, content, data quality, and provenance). ANDROMEDA can be also adapted when new sources are added or new requirements are specified. Furthermore, in ANDROMEDA the data integration process is done in a distributed manner, taking advantage of the available computing resources and reducing data communication costs.