Extensive Cooperative Caching in D2D Integrated Cellular Networks

Device-to-device (D2D) communication is a promising supplement to cellular networks, since it provides high rate transmission without changing network infrastructure. For a D2D integrated cellular network, caching popular content (e.g., multimedia files) at a base station (BS) or a D2D device near to a requesting user not only reduces content delivery delay, but also alleviates backhaul traffic load. In order to minimize content delivery delay, in this letter, we propose an extensive cooperative caching (EC-Caching) scheme, which allows inter-BS, inter-device and between-BS-and-device cooperation in content caching. Simulation results demonstrate that the extension in degree of cooperation between the caching nodes contributes significant performance gain in terms of content delivery delay and cache hit rate, especially in populated areas.