Web Services for Peer-to-Peer Resource Discovery on the Grid

Several features of today’s Grids are based on centralized or hierarchical services. However, as Grid sizes increase, some of their functions should be decentralized to avoid bottlenecks and guarantee scalability. A way to provide Grid scalability is to adopt Peer-to-Peer (P2P) models and protocols to implement non hierarchical decentralized Grid services and systems. A core Grid functionality that could be effectively redesigned using the P2P model is resource discovery. This paper proposes an architecture for resource discovery that adopts a P2P approach to extend the model of the Globus Toolkit 3 information service. The Open Grid Services Architecture is exploited to define a P2P Layer of specialized Grid Services that support resource discovery across different Virtual Organizations in a P2P fashion. The paper discusses also a protocol, named Gridnut, designed for communication among Grid Services at the P2P Layer.