Data Replication And Fault Tolerance In The Grid Environment

As the result of the increasing demand for calculative resource and calculative capacity, the grid technology has emerged. Its final goal is to realize resource share and coordinating work in virtual network environment and dissolve the information isolated island and resource isolated island.In the grid environment, it is necessary to high-powered frequently access and deal with a great deal of remote data for many applications. The data replication not only reduces network lag and bandwidth consumption when accessing long-range data, but also improves load balance of network, security and reliability of data. The choice of replication node and efficiency of the strategy will influence user's accessing long-range data resource. So based on the former researches of grid, this paper proposes a data replication strategy based on bid mechanism. Such strategy chooses replication node by means of bid. First, the system asks for sending biding information to all nodes according to replication request and then all nodes refer to the tender and the use of resources itself to work out bid scheme. Finally, the system chooses the best one among all bid schemes. Relative to the others, this strategy make users obtain storage resource with lowest cost, what's more, it settles the reward of the resource supplier via bid mechanism. In addition, we propose a new grid autonomic fault-tolerant service based on Globus fault-tolerant service, aimed to the failure of user tasks and node resources. This service provides users with effective strategies in three aspects: user tasks, system-level applications and system-level components. Grid users can get continual service by grid autonomic fault-tolerant service. Furthermore, the grid system will be more and more robust.