目前副本策略已经被广泛地应用于提高P2P系统的性能和可扩展性。随着越来越多的业务的发展,需要文件更新频繁以及网络的高度动态性,使得副本的一致性维护亦变得越来越重要。针对这个问题,研究在高度动态的网络环境下,将结点离线率和副本点与非副本之间的转换概率作为依据,构建维护责任点分担owner责任。并用分层式混合推拉式谣言机制传递更新信息,减少冗余信息。实验证明,新算法在更新过程中能维持高的更新成功率和较低的流量开销,更适应动态网络的扩展。
Replication is a prevalent way to improve the performance and extension as well as to reduce the query responding time in P2P system. Because current network may be dynamic with nodes frequently joins and leaves and objects updated highly for adapting to operation developmented, maintaining consistency of replications is more challenging in these environmented. This paper presented a region push then pull algorithm in highly dynamic networks. It is based on percentage of offline nodes and the transform ratio between replicated nodes and un-replicated nodes to decide the nodes which are responsible of easing the burden of owner. Besides, it can largely reduce the number of the duplicated messages. The experimental results show that the new algorithm has excellent consistency and lower messages overhead especially in dynamic environments,which is better adapted to the extension of dynamic P2P systems.