SVC-based caching and transmission strategy in wireless device-to-device networks

To address the explosively growing demand for mobile traffic, wireless device-to-device (D2D) networks have been introduced, where caching at user devices can be exploited to alleviate the burden on base stations. In this paper, we consider joint caching and transmission of scalable video coding (SVC) streaming over wireless D2D networks. We formulate a joint caching and transmission problem using integer linear programming to minimize the average download time for user, and prove that finding the optimal solution is NP-hard. A heuristic solution is proposed based on a two-phase sub-optimization problem focusing on caching and transmission decisions, which is solved by using relaxed linear programming. Simulation results show that the proposed scheme can significantly reduce the average download time in comparison with existing caching strategies.