A two-level patching scheme for video-on-demand delivery

Although patching has shown to be a simple and efficient technique for immediate media on-demand delivery, there is still much scope for further improvement compared with the lower bound of the server network-I/O bandwidth requirement. In this paper, a new technique of two-level patching scheme is proposed for the first time, in which patching channels are rearranged through merging and further patching. Simulation results show that the proposed two-level patching scheme outperforms the conventional patching technique by a significant margin. It even performs better than the dynamic skyscraper algorithm over a wide range of client request rates. Furthermore, it is reasonably competitive with hierarchical multicast stream merging (HMSM) at low to modest client request rates. Most importantly, the implementation complexity of our algorithm is much lower than the skyscraper and HMSM.