Abstract: By using the way of P2P, a P2P storage system was built. The nodes involved in the system were grouped by the predicted network distance, and then an overlay network which is maintained by super nodes was formed. By using the overlay network topological structure mechanism of maintenance, DHT data storage mechanism, data replication mechanism based on different frequency of data access and data restoration mechanism, the reliability of the system and the efficiency of data storage in system were promoted. The performance of the storage system was testified on the basis of the results of simulation experiment.

Key words: P2P storage system, Network distance, Grouping, Replication, Bandwidth