中文摘要：

P2P（peer-to-peer）的组织模式已经成为新一代互联网应用的重要形式,它为应用带来了更好的扩展性、容错性和高性能.P2P存储系统一直是研究界所关注的热点,被认为是P2P最具前途的应用之一.数据的持久存储是制约P2P存储系统发展的关键问题,也是其研究的难点.综述了P2P存储系统及数据持久存储相关技术的研究现状.首先概述了P2P存储系统的基本技术组成及其在不同应用环境中的优势,并介绍了数据冗余、数据分发、错误检测和冗余数据维护等多种持久存储的基本技术.在一个P2P存储系统研究框架下,介绍了目前知名的P2P存储系统及其使用的持久存储技术.对各种技术进行了详细综述和对比讨论,分析了各种技术的适应环境及优劣,指出了存在的问题和未来研究的方向.

英文摘要：

Peer-to-Peer （P2P） has been one of the most important architectures for Internet applications for its inherent scalability, fault tolerance, and high performance. The research of P2P storage systems is one of the hottest issues, and P2P storage system is regarded as one of the most promising P2P applications. However, to provide durable data storage is not trivial work and sets great barrier to real deployed systems. This paper surveys the P2P storage systems and techniques for durable storage. This paper first introduces the basic components of a durable P2P storage system and the advantages by using P2P architecture, and then introduces a series of techniques for durable storage including data redundancy, data placement, failure detection and data maintenance. Following the research framework, some typical P2P storage systems and their techniques are introduced. By a detailed comparison, the pros and cons of the techniques are discussed. In the end, the problems in current research and some future research issues are outlined.