Research On Durable Data Storage Mechanism In WAN Storage System Based On P2P

P2P (Peer-to-Peer) has been one of the most important architectures for Internet applications, as its inherent expansibility, fault tolerance and high performance features and so on. The research of WAN storage system based on P2P is one of the hot issues, and it is regarded as one of the most promising P2P applications. However, durable data storage is not a trivial work and a great barrier to WAN storage system. Firstly, the paper surveys some typical WAN storage systems based on P2P and the durable data storage of techniques they adopted. Secondly, this paper introduces and compares data storage redundancy of techniques, data storage placement of techniques, data storage failure detection of techniques and data storage maintenance of techniques in durable data storage of techniques in detail.To aim at the problem of durable data storage in WAN storage system based on P2P, this paper researches Byzantine fault tolerant productions of WAN storage system based on P2P in recent years. Then it summarizes the Fault tolerant demands and techniques in WAN storage system based on P2P, and the existing techniques of Byzantine fault tolerance. It analyzes and compares fault tolerant techniques of some typical systems in detail, explores some key issues of WAN storage system based on P2P, which should be improved, and discusses the trend of the development of Byzantine fault tolerance systems. It proposes a possible scheme framework to solve the problem in practical storage system.At the scheme framework, the nodes are grouped by the predicted network distance, then an overlay network which is maintained by supernodes is formed in this paper. 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 durable data storage in system are maintained.Based on the simulation experiment, the durable data storage performance in WAN storage system based on P2P is inspected and verified by compared with the performance contrast in typical Chord system about data storage location route inquiry hop, system average processing message counts at nodes join and quit, performance compare about dates restoration average time at nodes failed.