Minimizing Bandwidth Requirements for VoD Services with Client Caching
Hao Feng, Zhiyong Chen, Hui Liu · 2016
Due to the explosive growth in multimedia traffic demand, scalability and delivery efficiency of video-on-demand (VoD) services have become important issues. In this paper, we develop a joint cache allocation and multicast delivery scheme to minimize the average bandwidth consumption of VoD services with client caching under the zero-delay constraint. Specifically, we first propose a client caching enabled multicast patching (CCE-MP) mechanism which achieves the minimum bandwidth consumption given a certain cache allocation. Then we formulate the cache allocation problem into a convex problem, which can be effectively solved by a water-filling algorithm. In addition to the traditional full access pattern where clients watch the video entirely, we further consider the interval access patterns with uniformly distributed endpoints and fixed-size intervals. The impact of different access patterns on the cache allocation algorithm is also investigated. Simulation results indicate that the proposed scheme significantly outperforms other existing approaches, e.g., more than 50% bandwidth saving under a certain setting.