Social-Aware and Payment Incentivized Caching for D2D Communications

Content caching for Device-to-Device (D2D) communications is considered as a promising approach to solve the problem of data traffic explosion. However, due to users' selfishness towards strangers, they may not be willing to cache data for other nodes even within the physical reach of communication. In this paper, a social-aware and payment incentivized caching scheme for D2D communications is proposed to encourage user nodes to cache data for others actively and efficiently. First, we introduce social ties and payment as factors to form a system gain function. Then we consider the system gain function maximization, which is proved to be NP-hard. Finally, we advocate a greedy algorithm to find a suboptimal solution of this problem. Simulation results verify that the introduction of the payment ensures the user's realizability and the introduction of social ties has greatly improved the effectiveness of users.