基于延迟敏感的双向查询Chord系统  

Bidirectional Chord System Based on Latency-sensitivity

作　　者：王菁[1] 杨寿保[1] 郭磊涛[1] 周金洋[1] 

机构地区：[1]中国科学技术大学计算机科学技术系,安徽合肥230026

出　　处：《小型微型计算机系统》2007年第4期604-608,共5页Journal of Chinese Computer Systems

基　　金：国家自然科学基金项目(60273041)资助;国家"八六三"项目(2002AA104560)资助.

摘　　要：结构化对等网络(Peer-to-Peer,P2P)中的关键问题是有效地定位资源,Chord系统是构建在叠加层上的结构化P2P网络,但是该系统的构建没有考虑到网络层的实际情况,同时,现有Chord的顺时针查询算法没有充分利用逆时针方向上的邻居信息,从而导致定位资源的响应时间增加.本文采用基于延迟敏感的双向查询Chord系统来降低资源查找的延迟和开销.该系统根据节点和参考点之间的延迟对节点进行分组,减少平均响应时间;通过实现Chord上的双向查询,缩短搜索路径长度.理论分析和仿真实验表明该系统有效地降低了定位资源的响应时间.The key issue in structured P2P （peer to peer） is to locate resources effectively. Chord is a kind of structured P2P system based on overlay network. However, Chord construction doesn＇t consider the real network situations. At the same time, the clockwise searching scheme of original Chord doesn＇t make good use of the anti-clockwise neighbors＇ information. All these increase the latency and cost of locating resources. A bidirectional Chord system based on latency-sensitivity is proposed to decrease the latency and cost of locating resources. This system partitions the nodes according to the latencies among these nodes and the landmarks to decrease the average response time. And by the means of bidirectional query algorithm on Chord, the search path length is reduced. Theoretical analysis and simulations show that the system decreases query-response time greatly.

关 键 词：对等网络 CHORD 双向查找 延迟敏感 分布式哈希表 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]