基于局部需求的稀有资源主动复制与搜索机制  

Active Replication and Search Strategy of Scarce Resources Based on Local Demand

作　　者：梅红岩[1,2] 张玉洁[1,2] 孟祥武[1,2] 

机构地区：[1]智能通信软件与多媒体北京市重点实验室(北京邮电大学),北京100876 [2]北京邮电大学计算机学院,北京100876

出　　处：《软件学报》2015年第9期2418-2450,共33页Journal of Software

基　　金：国家自然科学基金(60872051);北京市教育委员会共建项目

摘　　要：非结构P2P网络中,已有的搜索协议对流行资源的搜索是有效的,但对于稀有资源的搜索是低效的.提高稀有资源的副本率,是解决其搜索低效性的根本方法.由于稀有资源在网络中的副本较少,其查询的点击率较低,因此,已存在的基于成功查询的被动副本复制策略不适合稀有资源副本流行度的提高.针对该问题,提出了一种稀有资源的主动复制与搜索策略,由拥有稀有资源的节点主动发起对稀有资源需求信息与需求节点的搜索,在搜索过程中,有效获取局部需求信息,将稀有资源主动复制到有需求的区域内及节点上,从而实现稀有资源的按需复制,有效提高其流行度和点击率.基于局部需求信息,提供3种不同的按需复制策略,并给出了一种稀有资源搜索算法.实验结果表明:这种稀有资源的主动搜索复制策略能够以较低的复制消耗和网络开销,有效地提高稀有资源的副本率,进而提高稀有资源的点击率.In unstructured P2P networks, the existing search protocols are effective for popular resources, but searching for scarce resources is inefficient. Improving copy rates of scarce resources is the main method to solve the search inefficiency. The query hit rates on scarce resources are lower as copies of scarce resources are small. So the existing passive copy replication strategies based on the success queries are not suitable for the improvement of rare resources popularity. To solve this problem, we propose an active replication and search strategy of scarce resources. In the search process, peers with scarce resources actively initiate the search for scarce resources. And local demand information is effectively obtained in the process of search, and then scarce resources are copied to the peers that have demands for the scarce resources. The method implements the on-demand replication of scarce resources to improve popularity and query hit rates of scarce resources. Based on local requirement information, we provide three different kinds of on-demand replication strategies and a rare resource search algorithm. Experimental results show that the active replication and search strategy of scarce resources can effectively increase copy rates of scarce resources with lower replication consumption and network overhead, and then improve the query hit rates of scarce resources.

关 键 词：PEER-TO-PEER 非结构网络 主动搜索 局部需求 

分 类 号：TP311[自动化与计算机技术—计算机软件与理论]