基于VBR多媒体流资源管理的研究

RESEARCH OF RESOURCE MANAGEMENT FOR VBR MULTIMEDIA STREAMS

在分布式多媒体系统中 ,连续媒体流采用压缩方式传输 ,以减小最昂贵资源网络带宽的使用 .但是压缩媒体流是变化位速率流 (VBR) ,在网络传输中产生突发情况 ,给网络资源管理带来了挑战 .本文在基于未压缩媒体流节资源管理方案基础上 ,提出 VBR节概念 ,把变化尺寸的突发的媒体帧拆分成网络发送包 ,采用周期性调度 ,平滑突发帧的传输 ,给出了 VBR节在保证流 Qo S基础上 ,CPU周期、带宽和缓冲区资源的分配公式 ,显示出通过调整调度包数量和适当增加缓冲区空间 ,可明显地节省网络带宽 。

The continuous media stream is usually transmitted with compression in order to reduce networks bandwidth, the much expensive resource, in distributed multimedia systems. But compressed media stream is VBR stream that generates brush in transmission, which the challenge is given to resource management in networks. The definition of VBR session is presented that segments brush media frame into packets of networks based on session non compression media stream in this paper. The packets are scheduled by periodic algorithm to smooth the brush frame. It addresses equations of allocating CPU period, bandwidth and buffer space resource to guarantee QoS. It shows that the network bandwidth is obviously saved by adjusting the number of packets scheduled and increasing appropriate buffer spaces and an experiment is done.