Proactive Caching Over Cloud Radio Access Network With User Mobility and Video Segment Popularity Awared

Caching at the edge of wireless networks is a promising means of alleviating the heavy burden of backhaul links and reducing the latency of transmission and handover in a cloud radio access network (C-RAN). Although some effective caching schemes have been introduced to C-RAN, most of them are not designed with consideration of both user mobility and video segment popularity, which have influence on the performance of wireless caching. Therefore, this paper investigates the above-mentioned two factors for a cache-enabled C-RAN, and proposes two proactive caching strategies that are based on user mobility only, and both user mobility and video segment popularity, respectively. We design a novel controller, which is able to fully utilize the computational and storage resources, and acts the role of cache decision making for the baseband unit pool and remote radio heads. Numerical simulation results demonstrate that the proposed schemes significantly outperform traditional strategies by 20% and 16% in terms of average data transmission delay and cache hit rate, respectively.