Segment-based random caching in device-to-device (D2D) caching networks

We consider a device-to-device (D2D) caching network, in which the wireless users act as caching helpers and can provide the proximal users popular files via the D2D links. Since the caching allocation strategy is the essential part, we investigate the caching schemes to improve the hitting probability. Specifically, we first propose a cut-off random caching scheme and further extent it to an optimal segment-based random caching scheme. Finally, we propose a sub-optimal scheme with low complexity. Simulation results show that our sub-optimal method has the similar performance with the optimal one and it outperforms the existing caching schemes.