Cooperative Willingness Aware Collaborative Caching Mechanism Towards Cellular D2D Communication

Abstract

In D2D communication, physically adjacent users can directly establish connections without transmitting through base station, which can improve the network performance. The cellular D2D caching technology can offload part of the traffic of the base station and effectively alleviate the data transmission pressure of the base station. However, there is no research on cache mechanism in cellular D2D network that consider the collaboration willingness of equipment (UE). Therefore, the cooperative willingness aware collaborative caching mechanism towards cellular D2D communication (CWCM) is proposed. First, a D2D UE cache capability estimation method is proposed, which comprehensively considers the cache space occupied by the local cache content and the actual cache space setting of the UE to estimate the cache capability of the UE. Second, a D2D UE service relationship perception method is presented in which the content cache and the content discard records are used to comprehensively consider the cooperative and non-cooperative behavior to sense the service relationship between D2D UEs. Third, a collaborative willingness awareness caching mechanism is designed by considering the cache capability of the UE and the service relationship between the UEs. Simulation results show that the proposed CWCM can greatly improve the cache hit rate, largely reduce the transmission energy consumption, and average delay.