中文摘要：

采用OGSAGT3实现一个新型VOD系统，从系统全局负载均衡和视频对象流行度两个方面讨论系统的节目调度策略，给出具体实现过程．用OptorSim网格模拟器模拟表明，该系统采用的节目调度策略大大降低了骨干网络的带宽需求，提升了整个VOD系统的服务能力．

英文摘要：

A new video-on-demand（VOD） system is implemented by using OGSA-GT3. The problems of program scheduling scheme in the system are discussed from the load balance and the popular degree of video object; and the method of the scheme＇s implementation is given. OptorSim is used to simulate the scheme. The results show that the scheme used in the system can decrease the consuming of backbone network＇s bandwidth greatly; thereby the service ability of the Video-on-Demand system is improved.