基于内容预期价值的内容中心网络缓存替换策略

Content-Centric Network Cache Replacement Strategy based on Content-Expected Value

缓存替换技术是内容中心网络的研究内容之一。相对于海量的内容数据,缓存空间总是有限的,良好的缓存替换策略可以提高缓存收益。考虑到内容在将来被请求的概率越大,预期访问时间距离当前时刻越近,其留存价值就越大,提出了一种基于内容预期价值的替换策略。该方案通过考虑内容流行度和预期访问时间到当前时刻的时间距离,构建内容预期价值函数,并据此将价值最小的内容替换出去。仿真实验证明,该策略相对于传统的缓存替换策略,可以有效提高缓存命中率、降低请求跳数,提高网络性能。

Cache replacement strategy is one of the research issues in content-centric networks.Compared with the massive amount of content data,the cache space is always limited,and good cache replacement strategies can increase cache gains.Considering that the greater the probability that the content is requested in the future,the closer the expected access time is to the current moment,the greater its retention value is,a replacement strategy based on the expected value of the content is proposed.This solution considers the content popularity and the time distance from the expected access time to the current moment to construct the expected value function of the content and replace the least valuable content accordingly.Simulation experiments indicate that this strategy can effectively improve the cache hit rate,reduce the number of request hops,and improve network performance compared to the traditional cache replacement strategy.