基于内容热度与节点介数的NDN网络缓存策略

缓存技术是数据命名网络（Named data networking，NDN）的关键技术之一. NDN传统的LCE缓存策略会造成较大的冗余. 改进的RCOne策略采用随机放置的方法，没有利用任何内容、节点信息，对网络缓存性能的提升有限. Betw策略只考虑到节点介数，导致高介数节点缓存更替频繁，当节点缓存容量远小于内容总量时，缓存性能下降. 为了解决这些问题，本文提出一种结合内容热度与节点介数的新型缓存策略HotBetw（Hot content placed on node with high Betweenness），充分利用内容与节点信息选择最佳的位置放置缓存. 仿真实验表明相对于典型NDN缓存策略，HotBetw缓存策略在提高缓存命中率、降低平均跳数方面具有很好的效果.

Cache Scheme Based on Content Popularity and Node Betweenness in Named Data Networking

Cache is one of the key technologies of named data networking(NDN). However, the basic cache scheme LCE (leave copy everywhere) in NDN leads to much redundancy. The RCOne scheme chooses the cache node randomly without using any information of content and node, which is limited in improving cache performance. The Betw scheme results in that the node has the more frequent replacement with the larger betweenness centrality, which will decrease the cache performance when the node''s cache capacity is far smaller than the total content amount. In order to solve those problems, a cache scheme named HotBetw is proposed in this paper based on content popularity and node betweenness to choose appropriate cache node along the content delivery path. The simulation results show that the HotBetw cache scheme can achieve higher cache hit ratio and reduce average request hop compared with existing schemes.