Caching in Large-Scale Cellular Networks with D2D Assistance

This paper deals with edge caching and investigates a cellular network where both base-stations (BSs) and distributed devices have caching capabilities. The proposed caching policy allows each device to cache files according to the user’s preferences while the most requested files are cached in the BSs. In this way, a three-level hierarchical connectivity scheme is employed, where a file request is satisfied with priority order by i) the closest paired device, ii) the closest BS, iii) the backhaul network. By using stochastic geometry, we derive the success probability of a requested file. Moreover, we model the capacity of the backhaul link and evaluate the delivery delay of a file. We show that our proposed protocol increases the success probability and reduces the delivery delay.