Distributed Metadata with the AMGA Metadata Catalog
Catalog Services play a vital role on Data Grids by allowing users and applications to discover and locate the data needed. On large Data Grids, with hundreds of geographically distributed sites, centralized Catalog Services do not provide the required scalability, performance or fault-tolerance. In this paper, the authors start by presenting and discussing the general requirements on Grid Catalogs of applications being developed by the EGEE user community. This provides the motivation for the second part of the paper, where they present the replication and distribution mechanisms they have designed and implemented into the AMGA Metadata Catalog, which is part of the gLite software stack being developed for the EGEE project.