A caching strategy based on many-to-many matching game in D2D networks

Wireless edge caching has been proposed to reduce data traffic congestion in backhaul links, and it is being envisioned as one of the key components of next-generation wireless networks. This paper focuses on the influences of different caching strategies in Device-to-Device (D2D) networks. We model the D2D User Equipments (DUEs) as the Gauss determinantal point process considering the repulsion between DUEs, as well as the caching replacement process as a many-to-many matching game. By analyzing existing caching placement strategies, a new caching strategy is proposed, which represents the preference list of DUEs as the ratio of content popularity to cached probability. There are two distinct features in the proposed caching strategy. (1) It can cache other contents besides high popularity contents. (2) It can improve the cache hit ratio and reduce the latency compared with three caching placement strategies: Least Recently Used (LRU), Equal Probability Random Cache (EPRC), and the Most Popular Content Cache (MPC). Meanwhile, we analyze the effect of caching on the system performance in terms of different content popularity factors and cache capacity. Simulation results show that our proposed caching strategy is superior to the three other comparison strategies and can significantly improve the cache hit ratio and reduce the latency.