CT-Cycloid:一个基于Cycloid的抗Churn的P2P系统  

CT-Cycloid:a Novel Churn-Tolerant P2P System Based on Cycloid

作　　者：陈敬[1] 禹继国[1] 

机构地区：[1]曲阜师范大学计算机科学学院,山东日照276826

出　　处：《计算机技术与发展》2010年第7期244-249,共6页Computer Technology and Development

基　　金：国家自然科学基金(10471078);山东省中青年科学家奖励基金(2005BS01016);山东省科技攻关计划(2009GG10001014);山东省教育厅科研项目(J07WH05)

摘　　要：Cycloid是一种常数度结构化P2P覆盖网,它具有高扩展性、自组织、自适应开销低等优点,然而像所有其它的常数度P2P覆盖网一样,它不能很好地适应高churn环境。为解决这一问题,在一个简单而新奇的设想的启发下,基于生存期的策略和角色划分机制被应用来对Cycloid的设计进行改造,构造了一个基于Cycloid的具有高抗churn能力的结构化P2P系统——CT-Cycloid。在CT-Cycloid系统中进行路由和定位的开销是O(logS),远低于一般系统中的O(logN)(S=N/logN)。大多数节点到来和离开时仅仅需要发送一条一跳到达的信息,节点的失效会很快被检测到,网络很快得以恢复稳定。理论分析和仿真实验都证明了CT-Cycloid与Cycloid相比查询路径更短,适应高churn环境的能力更强。As an excellent scheme of constant-degree P2P overlay networks,Cycloid has high scalability,and pays low cost for self-organization and self-adaptation.Similar to other constant-degree P2P overlay networks,Cycloid cannot work very well in high-churn-level environments.To overcome this,modify Cycloid and propose CT-Cycloid,a novel churn-tolerant P2P system based on Cycloid,by applying a simple and novel scheme,a lifespan-based strategy and a role-division mechanism.The overhead of the novel system for routing and localization is O（logS）,which is significantly lower than O（log N） in common P2P networks,where S=N/logN）,and N is the number of nodes in systems.Most nodes in CT-Cycloid just need to send a one-hop message when join or leave the overlay network.Nodes failure can be found quickly,and can be dealt reasonably.Both theoretical analysis and simulation have proved that CT-Cycloid needs smaller number of hops in searching and has higher churn-tolerant capability than Cycloid.

关 键 词：P2P覆盖网 Cycloid覆盖网 CHURN 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]