内容中心网络中基于缓存压力的选择性缓存机制

内置缓存机制是内容中心网络(Content Centric Networking,CCN)研究的关键问题之一.现有的CCN缓存机制在缓存节点的选择时往往缺乏对节点缓存状态和负载情况等动态信息的综合考虑,因此无法准确反映节点间的缓存状态差异,进而影响了缓存决策的合理性.提出了一种基于缓存压力的选择性缓存机制(Cache Pressure Based Selective Caching,CPBSC).该机制利用节点的缓存占用率和缓存替换率评估节点的缓存压力,并结合内容的流行度实现缓存节点的合理选择.同时,根据内容的请求率和兴趣分组的剩余生存时间评估不同内容的缓存价值,以此实现缓存内容的合理替换.仿真结果表明,CPBSC有效地优化了缓存资源利用率,并显著提高了系统的整体缓存性能.

Cache Pressure Based Selective Caching Scheme for Content-centric Networks

In-network caching scheme is one of the key technologies of Content Centric Networking (CCN). In some existing CCN caching schemes, the dynamic information of cache state and load condition are not fully considered so that the differences of cache state between nodes cannot be reflected accurately, which affects the reasonability of caching decision. In this paper, a Cache Pressure Based Selective Caching Scheme (CPBSC) was proposed. In this scheme, the cache occupancy rate and cache replacement rate were used to estimate the cache pressure of node. According to the cache pressure and content popularity, the caching nodes were rationally selected. Meanwhile, the content replacement is implemented based on the cache value of content which is evaluated by the content request rate and the residual time to live of Interest packet. Simulation results show that CPBSC effectively increases the resource utilization and improves the whole cache performance.