A Proactive Caching Scheme Based on Content Concentration in Content-Centric Networks

Content-Centric Networking (CCN) provides a new networking paradigm to overcome the challenges of the current Internet and better support the content-oriented services. In-network caching is one of the core technologies for optimizing content distribution and has been attracting ever increasing attention. In the current CCN caching schemes, the caching decision is only implemented during the content response process after the content which matches the user request is found, which lacks the capacity of proactive content advancement. This paper borrows the idea of molecular diffusion and introduces the conception of content concentration into the caching decision to analytically model the user demands for different contents in different network regions, and then a proactive caching scheme based on content concentration is proposed. In this scheme, the content replica can be proactively pushed from the high concentration region to the low concentration one to realize the fast deployment of content cache replicas and the dynamic adjustment of the cache location. Furthermore, a probabilistic content placement method is also implemented by synthetically considering the content popularity. The simulation results show that this scheme can effectively improve the cache hit ratio and shorten the delay involved in content search and response