Selection Policy: Fighting against Filter Effect in Network of Caches

Abstract

Many Information Centric Networking (ICN) proposals use a network of caches to bring the contents closer to the consumers, reduce the load on producers and decrease the unnecessary retransmission for ISPs. Nevertheless, the existing cache management scheme for the network of caches obtain poor performance. The main reason for performance degradation in a network of caches is the filter effect of the replacement policy. A cache serves the requests that generate cache-hits and forwards the requests that generate cache-misses. This filtering changes the pattern of requests and leads to decreased hit ratios in the subsequent caches. In this paper, we propose a coordinated caching scheme to solve the filter effect problem by introducing the selection policy. This policy manages a cache such that: i) the cache obtains a high hit ratio ii) the missed requests from the cache can be used by subsequent caches to obtain a high hit ratio. Our coordinated selection scheme achieves an overall hit ratio of a network of caches equivalent to that of edge routers with big caches. Moreover, our scheme decreases the average number of evictions per cache slot by four order of magnitude compared to the LRU universal caching.