摘要
研究了点播业务在广电IP、DVB通道共存环境下支撑问题,提出一种基于稳态带宽的联合通道调度PBHS(Prediction Based Hybrid Schedule)算法。此算法充分发挥了IP单播和DVB广播优势,实现对不同特征(带宽、时长、热度)点播片源的自适应接纳决策(单播、周期性补丁和广播)。PBHS调度算法分为带宽不受限和受限两部分:前者依据对稳态带宽的估计,与基于流行度的带宽调度算法相比,带宽资源需求可减少约20%;后者依据带宽分配效能因子,与基于流行度的带宽调度算法相比,确定性的拒绝对部分片源请求的同时,降低用户拒绝率。
For video on demand bandwidth allocation problem,joint channel bandwidth scheduling based on static bandwidth prediction-PBHS （Prediction Based Hybrid Schedule） algorithm is proposed in this paper.This algorithm takes advantage of both IP and DVB bandwidth resources to realize adaptive admission to VOD videos of different characteristics （bandwidth,duration,popularity）.It consists of two parts：non-limited and limited bandwidth algorithms.The former is based on steady-state bandwidth,bandwidth requirements can be reduced by about 20% than popularity based bandwidth scheduling algorithm,and the latter one is based on allocation performance factor,comparing with popularity-based bandwidth scheduling algorithm,which not only reduce user rejection rate but also deterministically deny requests for certain videos.
出处
《微计算机应用》
2010年第9期47-62,共16页
Microcomputer Applications
