Social-Aware Incentivized Caching for D2D Communications

The device-to-device (D2D) channels allow content sharing when two devices are in close proximity, which can help improve resource utilization and network capacity. The data caching is introduced in D2D networks to enable the quick data access in mobile networks. Due to the selfish nature of users, they wish to get as much replication as possible in the opportunistic connections, seeking to maximize their own profits. However, caching data for other nodes may result in additional cost to the node serving as cache, where the cost is invoked by the cache placement of cache nodes and accessing cost of other nodes. In this paper, we propose a social-aware caching game to incentivize nodes to cache data for others. In the game, we consider the social ties and physical distance as the factors to formulate the caching cost. We obtain the Nash equilibrium of the game and propose a social-aware algorithm to minimize the total cost of getting object data in the network. The extensive simulation results show that our algorithm gains significant cache benefit.