摘要
近年来,网络实时流媒体获得了越来越广泛的应用,引起了学术界和工业界的广泛关注。然而实时多媒体对传输时延、时延抖动以及网络带宽有着很高的要求,这对于在不可靠的网络环境下提供服务质量保证无疑是一个重大的挑战。以小波分析模型为基础,对VBR实时视频流的时延以及时延抖动进行深入的研究。在此基础上,通过Mat-lab仿真的方法对视频流的时延和时延抖动进行定性的分析和研究。结果表明,当节点服务速率固定时,时延和时延抖动初始时随着缓存的增加而增大;但当缓存增加到一定程度时,VBR视频流数据包的时延和时延抖动将趋于稳定。另外,通过实验还发现,当缓存固定时,随着服务速率的提高,VBR视频流的时延和时延抖动都将急剧下降。这些研究结果有助于进一步深入了解VBR视频流的通信特性及其传输规律,为提高多媒体网络的性能奠定良好的基础。
Real-time media streaming has seen increased demand on the Internet in recent years, and has drawn tremendous attention from both academia and industry. Multimedia applications in real time have rigid requirements on bandwidth,delay and jitter, and especially identify significant challenges for providing QoS guarantees in lossy networks. This paper presents an analytical study of the delay and jitter for real-time media streaming using the wavelet model for VBR streams. On this basis, a series of Matlab simulation experiments are designed and conducted, and the results are qualitatively analyzed and investigated. Our study shows that the delay and jitter of the video traffic increase as the huffer size is increased, in case of fixed service rate of the nodes. However, they tend to he stable when the buffer size increases to a certain degree. In addition, we find that, with the increasing of the sending rate, the delay and jitter decrease sharply when the buffer is fixed. We believe that this work could contribute in understanding the characteristics of realtime video traffic and transmission process of VBR streams, in performance improvement of multimedia networks as well.
出处
《计算机科学》
CSCD
北大核心
2008年第10期106-109,共4页
Computer Science
基金
国家自然科学基金资助项目(项目编号:60673185)
关键词
流媒体
通信突发性
时延
抖动
多分辨率分析
Media streaming,Traffic bursty,Delay,Jitter,Multi scale analysis
作者简介
王军元 研究生，主要研究领域包括多媒体视频流特性研究、网络流量的自相似特性研究等；
白光伟 教授，博士后，主要研究领域包括网络体系结构和协议、无线移动Internet、多媒体网络、网络系统性能分析、评价等。
