File names and Object handles . The ability to name objects in a manner independent of physical attributes that bind them to the Grid is also essential. Globus uses URLs to identify files, Sun's Jini uses references and proxies obtained from the directory services to identify resources. The following are the core services that must be abstracted by the APIs. There are three basic resource services.
Discovery refers to the service by which new resources and located on the network.
This may be invoked when a new service is added to the system or when a task request resources for which a resource handle is required for job execution. Allocation and Leasing refers to the process by which specific resources are bound to job objects during execution. Java Jini has a complete and sophisticated resource discovery system. Globus MDS provides the discovery system in that environment. In Condor, the matchmaker service proved a different model for resource discovery.