Replacement based content popularity and cache gain for 6G Content-Centric network

In Content-Centric network (CCN), the capacity of router nodes caches the contents to satisfy the requests from subsequent consumers, and reduce the network overhead. Considering the limited cache capacity, the update of cached contents becomes a key element affecting the caching performance for the future 6G network. In this paper, a replacement strategy based content popularity and cache gain (PGR) is proposed for 6G-CCN. In the proposed scheme, the popularity of contents in the current cycle is determined according to the time interval and frequency of consumers' requests. In addition, the distance between the router node and consumer affects the gain of caching. Further considering the dynamic popularity of content and gain of caching, a realistic content value function is provided. When the cache space reaches the upper bound, for the router node, the existing content with lower value will be replaced by newly arrived content with a higher value. Simulation results show that, compared with the conventional least frequently used (LFU) and least recently used (LRU), the proposed replacement strategy can effectively improve the space utilization and cache hit rate of router nodes, as well as reduce the average hops of consumers' content acquisition for 6G-CCN. (C) 2020 Elsevier B.V. All rights reserved.