ABSTRACT
The past few years have witnessed a rapid development of grid computing systems and their applications. Information services play a crucial role in grid computing environments to facilitate the discovery of resources and services. Existing work on information services, notably the Monitoring and Discovery System (MDS4) [1] of the Globus middleware [2], has advanced the research in this fi eld. MDS4 adopts a hierarchical tree structure to distribute its monitoring load across a virtual organization (VO), in which every node is running an index service monitoring its resources and pushing this information up to a master index server. Thus a VO has a central point for registering the state information of computing resources involved in the VO.
