Some Views on Building Computational Grids Infrastructure

This paper gives some opinions about grid bottleneck problem, and makes some suggestions about grid structure. It also introduces how to construct the global grid with sub grids, and to make use of the advantages of administrative hierarchy. The paper presents the conceptions of static resources, dynamic resources and the ways of scheduling resources. Also, the functions of resource marketplace are discussed. Finally, we describe the relationship, function and structural the principle of virtual organizations. 1 Some views on the improvement of grid structure There are bottleneck problems [10] not only in five-layer hourglass architecture but also in OGSA (Open Grid Services Architecture) [8]. It cannot be settled only by middleware. Some changes are needed in grid structure [4]. Because of the heterogeneity and scalability of grid structure, it makes us have to use Internet administration mode to build grid organizations. We could change local networks into local grids, namely sub-grids, and then link these sub grids together. Each sub grid can be looked as a node. They can be connected to form a global grid [7]. A grid management server should be set in the sub grid. It is good to make use of local network servers. The globus is run on it. The users access sub grids through web pages. Administrative hierarchy is used in them. Firstly, schedule of tasks and resources are carried on in a sub grid. If there are not enough resources, the task can be scheduled between other sub grids. It can be handed up global grid and apply for new resources. In order to translate protocols between sub grids, “half gateway” should be set on each node. We can use XML to do it. Taking administrative hierarchy could reduce the remote communication, which can decrease remote access, remote replica catalog and error in communication. It can avoid restriction of network bandwidth, and resolve the bottleneck problem with the integrated schedule management system. It is convenient to change and expand grid structure.