Design of a Scalable Peer-to-Peer Information System Using the GT4 Index Service

Grid applications need efficient access to information about available resources and services. Typically, this access is provided by information services that are often organized as hierarchical systems for better scalability and performance. As the number of types and instances of information services increases, it has become challenging to set up these hierarchies efficiently. We describe the design and implementation of an information system that forwards queries among GT4 index services using an unstructured peer-to-peer overlay network. Our initial measurements show that the performance of the peer-to-peer system scales better than a centralized index service. We also discuss simple optimizations that can significantly improve system performance.