一种新的P2P直播系统共享机制的测量、分析与建模  

Measurement,Analysis and Modeling of a New Sharing Mechanism in P2P Living Streaming System

作　　者：危婷[1] 邓光青[1] 陈常嘉[1] 李纯喜[1] 

机构地区：[1]北京交通大学电子信息工程学院,北京100044

出　　处：《北京邮电大学学报》2011年第6期59-63,共5页Journal of Beijing University of Posts and Telecommunications

基　　金：国家重点基础研究发展计划项目(2007CB307101-1);国家自然科学基金项目(60772043;60672069)

摘　　要：通过网络测量破解流媒体视频软件PPStream(PPS)直播系统的缓存结构和共享机制发现,与软件PPIive(PPL)滑动的共享窗口不同,PPS具有跳跃的共享窗口.利用"窗口跳跃模型"分析了PPS的共享机制对节点间互惠关系的影响,发现跳跃的共享窗口将造成节点相位波动.根据该相位波动特征建立模型来描述处于不同相位的人数.数值评估与系统仿真结果表明,该模型能很好地反映带宽资源争抢造成节点相位波动的特征,有利于进一步完善系统的带宽分配策略,以保证节点的播放进度.Peers＇ buffer structure and its sharing mechanism in peer to peer stream （PPS） live system are figured out. It is found that peers have jumping sharing window in PPS, different from peer to peer live （PPL） with sliding sharing window. The impact of sharing mechanism on the reciprocal relation between peers is analyzed by a window jumping model. It is also found that the sharing mechanism in PPS can result in peers＇ phase fluctuation. Based on the fluctuation features. A model to describe the user population of different phases is developed. Numerical evaluation and system simulation show that the model can well reflect the fact that the contention on bandwidth resources contributes to the peers＇ phase fluctuation. It brings insights to the work of further improving the bandwidth assignment strategy and peers＇ playback quality.

关 键 词：PPLIVE PPSTREAM 直播 缓存结构 共享机制 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]