The job of the OGSA is to build on the grid service specification (Open Grid Service Infrastructure, or OGSI) to define architectures and standards for a set of "core grid services" that are essential components to every grid. As we have discussed in the previous chapter, a set of core OSGA use cases are developed, which forms a representative collection from different business models (e.g., business grids and science grids) and are used for the collection of the OGSA functional requirements. We have identified some core basic functions across all the grid services.
Let us now further explore the details of these core platform services and their definitions in the context of OGSA and their interrelationships. We are assuming that these core grid service components must be present in every OGSA-based interoperable Grid Computing framework for the best quality of control features.
As shown in Figure 8.1, the basic OGSA architectural organization can be classified into five layers :
native platform services and transport mechanisms
OGSA hosting environment
OGSA transport and security
OGSA infrastructure (OGSI)
OGSA basic services (meta-OS and domain services)
Figure 8.1. OGSA core platform components ”an IBM vision on OGSA and integrated software components.
The above defined OGSA layers form the foundation for new high-level management applications and middleware Grid solutions and new class of Grid applications.