Resource Discovery in Virtual Organisations
In many existing VOs, a centralised resource index provides the functionalities to publish and discover resources (Foster, Kesselman, & Tuecke, 2001; Winton, 2005). Using a centralised resource index, a resource can be quickly found and consumed. However, the centralisation of the resource index service raises the issues of scalability caused by the limitation of resources at the index node, such as network bandwidth, CPU capability and storage space. Moreover, the centralisation of the resource index also introduces a single-point-of-failure to the system. The index node centralises all responsibilities for publishing and handling enquiries about resources. Once the resource index fails, all the information about accessible resources will be unavailable.
To reduce the problem of single-point-of-failure, each network node should have the capability to efficiently discover desirable resources by interacting with connected nodes. In SWEVO, each Grid node does not rely on a centralised index to provide resource discovery service, which can support and co-operate with each other in a P2P manner to quickly discover accessible resources to support real-time decision making.