Replica Management Key Problems Of Data Grid Based On GLOBUS

Data Grid is a direction of distributed and parallel processing technology.The goal of Data Grid is to realize sharing of heterogenous resources that located all over the world. Data replication management is the core technology and soul of Data Grid.Replication can reduce access latency,improve data locality,and increase robustness,scalability and performance,and balance the loads for distributed applications.Excellent resources replication management strategies are important to improve the Qos in Data Grids. Data Resouces replication management in the grid can reduce the communication cost on solitary service site.It also has good effect on reducing the bandwidth consumption caused by frequent remote access and balancing the load of global grid.This paper is based on the national important project, analyzes the topology structure of the Data Grid,goes into the key techniques,and points out the meagerness of applying various resource replication management techniques which are using into Data Grid now.Then,this paper analyzes the Data Grid resource replicaton management in Internet enviroment,and make out the characteristic and reasons for introducing the storage subregion model in the Data Grid.Based on previous research,the major research works and initiative points in this article are:Firstly, this article discusses the development of technology of Data Grid to manage grid resource replication, and pionts out the problems of Data Replica manage techniques,then introduces the works in this article.Secondly,introducing the Storage Subregion structure.proposing a data replication strategy based on Storage Subregion. including intra-subregion and inter-subregion strategies.Discussion indicates that the new strategies improves the user'access time and bandwidth comsumption of the Internet.Thirdly,proposing a data location strategy(RLABOG) based on Storage Subregion Structure.Proposes a three-level structure of replica location and the Replica Location Algorithm Based On Giggle(RLABOG).Using the strategy(RLABOG) reduces the access time and improves the system performance.Finally, because in the research of grid resource replication management,it is unnecessary to use real systems to evaluate the performance and accuracy of the algorithms.Usually, emulators are used to handle with it.Several grid emulators are illustrated in this article.OptorSim,a grid replica modeling and emulation toolkit,is introduced in details.Finally,with the help of Optorsim Toolkit,the emulation of data grid replication strategy with QoS requirements is realized.The experiment results show that the strategy present in this article is feasible. It improves the performance of data grid in the Internet enviroment.