| 摘要: |
| 在视频点播系统中.流调度算法通过降低服务延迟和提高服务效率等措施,可显著提高系统服务能力.提出了一种新的流调度算法--PeriodPatch.该算法在Patching算法的基础上引入了周期调度的规则.Period-Patch算法可以通过少数有序生成的组播节目流提供大量TVOD(truevideo_on_demand)级服务.PeriodPatch算法还保证系统在资源耗尽的情况下,可以提供高效、可预测的NVOD(nearvideo_on_demand)级服务.仿真结果表明,PeriodParch算法在TVO |
| 关键词: 流调度 周期 补丁流 VOD(video-on demand) |
| DOI: |
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| 基金项目:国家自然科学基金资助项目(69973025);国家重点基础研究发展规划973资助项目(G1999032700) |
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| A Stream Scheduling Algorithm Based on Period-Patching Strategy |
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XIANG Zhe,ZHONG Yu zhuo,XIAN Weiquan
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| Abstract: |
| Stream scheduling algorithm used in video_on_demand (VOD) system can largely increase system service ability by eliminating the service latency and improving the system efficiency. In this paper, a novel stream schedule called PeriodPatch is proposed. On the basis of Patching, a PERIOD rule is introduced, so that multicast streams are created orderly and fewer multicast streams are needed for the true video_on_demand (TVOD) service. Furthermore, PeriodPatch schedule ensures that the system can provide near video_on_demand (NVOD) service with a predictive andacceptable latency to the client if resource are exhausted out. The simulation results show that PeriodPatch is more efficient than others, with respect to both system resource required for TVOD service and average client waiting time (service latency) for a fixed available resource. In conclusion, the PeriodPatch is an efficient and economical stream schedule for VOD system. |
| Key words: stream scheduling period criterion patching stream video -on -demand |