Study of patching-based and caching-based video-on-demand in multi-hop WiMax mesh networks

In this work, we study two cross-layer techniques, the Patching-based scheme (PS) and the Caching-based scheme (CS), to provide video-on-demand (VoD) in the multi-hop WiMax mesh networks. PS consists of an efficient and lightweight multicast routing technique as well as the Patching technique in the application layer. Although PS improves the scalability of the system, the server has to launch extra Patching streams for later users in the multicast group. CS caches the video content in the subscribe stations of the mesh network. The cached video data can be used to accommodate later request. Both approaches employ a novel joint solution of admission control and channel scheduling for video streams in the lower layer. This joint solution guarantees the data rate for the admitted video streams, which is crucial for real-time video streaming application. We used simulation to study the performance of PS and CS under real system settings.