A cluster-based file replication scheme for DHT-based file backup systems

DHT-based file backup systems can provide efficient mechanisms for resource placement and lookup. However, these systems must deal with irregular and frequent join/leave of nodes and the problem of load unbalancing between nodes. This paper presents an efficient file replication scheme based on DHT identifier space clustering in order to guarantee data availability and support load balancing for DHT-based file backup systems. The main idea of our method is to divide a DHT network into a number of clusters, each of which locally stores and maintains data chunks of data files to guarantee the data availability for backup data files even in the case of node churn occurred in the network. Further, backup nodes are selected among high-capacity nodes in clusters to achieve a good degree of load balancing. Simulation results demonstrate the effectiveness of our proposed scheme in comparison with other file replication schemes.