LAUSR

UDN is considered as a promising technique to boost the network capacity by reducing the path loss between the base station and UE for the upcoming 5G mobile communication, while the backhaul capacity has become the bottleneck in huge data traffic generated by UEs. One effective approach to coping with the bottleneck is caching the content at the edge of UDNs. Taking advantage of D2D communication, not only SBSs but also UE can serve as cache nodes to help others for data access by sharing a channel to directly communicate with each other, thus tackling the bandwidth limitation of backhaul links. However, due to the selfish nature of mobile users in the network, incentive is needed for UEs to cache for others. In this article, the data caching incentive problem in UDNs is studied by exploring caching cost of SBS and social factors among UEs. A social group utility maximization (SGUM) game is exploited to motivate data caching among SBSs and UEs. Based on SGUM, a socially motivated caching approach is proposed. The evaluation of the proposed socially motivated caching approach is provided and compared to baseline caching schemes. The corresponding results and observations support the vision of a socially motivated caching paradigm for the future UDNs.