VGID: A Virtual Hierarchical Distributed Grid Information Database

In large-scale grid applications, relationship between VOs is not simple information aggregating for autonomy and visiting security. This paper presents a virtual grid information database (VGID) which implements a hierarchical and distributed information management mechanism. An information model is presented with extensible resource metadata management and hierarchical information organization that manages storage-independent resources into a global information structure according to logical relations between resources. Local information database is built within a domain (VO), which includes information collection, storage, and query, as lots of information service has done. Based on dynamical domain information management with topology service and distributed query mechanism, local information databases are integrated to provide a user-transparent global information view. VGID supports standard XPath statement, and index-based query process is tested to be efficient. VGID has been applied to information service of ChinaGrid.