Prefix Caching for Video Streaming in Wireless D2D Networks

This paper introduces a new prefix caching strategy for video streaming in wireless device-to-device (D2D) networks. Each user caches several initial sequential segments of video files and can share their cached parts via D2D communications. Moreover, video playing and downloading happen simultaneously. We evaluate the system performance by playback delay rather than traditional download delay. Specifically, we formulate the average playback delay minimization problem in terms of cache placement. By relaxing the integer constraints of the decision variables, the original problem becomes convex and then we can lind a lower bound of the optimal solution. Next we propose a greedy algorithm to solve the original minimization problem. And extensive simulation results reveal that our proposed video caching strategy has great performance in comparison with heuristic benchmark schemes.