针对P2P模式下视频流媒体直播系统的数据传输策略用改进的模拟退火算法进行了优化。以全局规划的思想建立了P2P视频流媒体的数据传输策略数学模型VMDTSA-P2P,模型充分考虑了可用出口带宽和可用性时间对播放连续性的影响,把它们作为获取最优解的目标函数因子,并用改进后的模拟退火算法进行解的寻优,相比于传统的数据传输策略,在具有大量用户的情况下加快了新节点从伙伴节点中选择数据块提供节点的速度,并且保证得到近似最优的数据块提供节点组合,减少了视频流媒体直播系统播放的延迟,从而提高了播放的连续性、流畅性,保证了视频播放的质量。通过该算法在模拟P2P系统中的实现,验证了该算法在P2P系统中对数据传输的准确性和高效性。
An algorithm optimization was made with improved simulated annealing algorithm aimed at data transmission strategy of streaming media system in P2P networks. According with global layout, a mathematic model have been established for data transmission strategy of streaming media system in P2P networks named VMDTSA-P2P, which completely have considered the affection of both the out-bandwidth and the available time, and take them as the object function for getting the optimum solution. It also optimized the solutions with improved simulated annealing algorithm. Compared with traditional data transmission strategies, this improved algorithm accelerates the speed of new nodes choose the data provider from its partner nodes when there are lots of users and insures the solution of the data provider is approximate the best. Thus, the play delay of the streaming media system is decreased and the quality of video playback is increased. By realizing it in a simulated P2P system, the accuracy and the efficiency were both verified in the simulation.