Layered Hierarchical Caching for SVC-Based HTTP Adaptive Streaming over C-RAN
Zhilong Zhang, Danpu Liu, Yaxiong Yuan · 2017
In recent decade, wireless networks face a large challenge of delivering HTTP adaptive streaming (HAS) due to the dramatic increase of traffic. Content caching is an effective method to relieve the burden of networks and has attracted considerable attention. Although some schemes have been investigated for content caching in cloud-based radio access networks (C-RAN), most of them were not designed for HAS. In this paper, we address the caching problem for SVC- based HAS over C-RAN. We propose a caching strategy with considering the layered property of video, the hierarchical caching architecture of C-RAN and the distribution of downloading rates. To our knowledge, no one has designed a caching scheme from such a perspective. A 0-1 programming problem is formulated to minimize the amount of backhaul traffic. Base on theoretical analysis and problem solving, a layered hierarchical caching algorithm is proposed which can provide an approximate ratio of 1#x002F;2. Simulation results are illustrated to show the effectiveness of our proposed method.