基于缓存开销的信息中心网络缓存协作策略

摘要

In-network caching is one of the core issues in information-centric networking (ICN) which will directly restrict the data dissemination performance of the network. Considering the cache cost contains not only the path cost raised by accessing a cache node on the path but also the replacement cost of old information, a path and node cost based cooperative caching strategy (PNC3S) is proposed. The PNC3S considers the path cost and replacement cost comprehensively,and whether information matches a node or not depends on the total cost. Then the optimization algorithm is introduced into the proposed strategy to make caching decision. The simulation experiments demonstrate that the proposed PNC3S, compared with CEE (cache everything everywhere) and LCD (leave copy down), improves such performance as cached information ratio,server load ratio,average link utilization ratio and hop reduction ratio.%网络化缓存策略影响ICN网络的传输性能,考虑到缓存执行时的开销不仅包含访问缓存节点时的路径代价,还应包含替换旧信息的替换代价,因此提出一种基于路径访问代价和节点替换代价的缓存协作策略(path and node cost based cooperative caching strategy,简称PNC3S).该策略对两种代价进行整体考虑,将代价总量作为是否进行信息与节点匹配缓存的依据,对提出的策略模型进行优化分析,将最优解作为缓存部署方案.实验结果表明,与CEE,LCD策略相比,PNC3S可以改善网络的信息缓存率、服务器的负载率、网络链路平均利用率,以及访问跳数减少率.