SOSC:一种基于自组织语义聚类的P2P查询路由算法

SOSC:A Self-Organizing Semantic Cluster Based P2P Query Routing Algorithm

在没有辅助机制的条件下,非结构化P2P网络资源定位技术的效率比较低,很难同时获得较低的查询延迟、少量的定位成本和较高的查询命中率,为此,提出了一种基于自组织语义聚类的P2P查询路由算法SOSC.SOSC算法通过直接用节点共享资源的关键词频率向量表达节点语义,各节点均试图与最相似的节点建立邻居关系,以及以指数衰减方式传递节点语义向量,创造性地解决了对等计算环境中聚类语义的表达和传递问题,使得节点可感知周围节点的语义层次,从而使得各节点均可以语义聚类为基础进行快速路由.分析和实验均表明,SOSC算法具有较小的路由延迟、较低的查询代价和较高的查询命中率.

The resource location of unstructured P2P network is usually with low efficiency,and whether a routing message walks in the right direction is not assured.Therefore it is hard to achieve low latency and high query hit rate with low cost under no other supporting mechanism.In this paper,we present a self-organizing semantic cluster based P2P query routing algorithm SOSC.SOSC first categorizes resources shared by each node,and then expresses the semantic of each category by a frequency vector.All of a node＇s categories together express its shared resource semantic.Each node tries to establish links with nodes which have most similar category semantic,and therefore SOSC tries to make nodes clustered according to their shared resources semantic.What is more,SOSC transmits a node＇s semantic in P2P network by exponentially decaying its keywords frequency vectors of all of its categories.By this way,SOSC creatively solves the problem of cluster semantic expressing and transmitting in a totally distributed environment.SOSC makes a node feel the semantic hierarchy of the semantic of its nearby nodes.Analysis and experiment results show that SOSC is able to achieve high query hit with small routing latency and query cost.