Nevertheless , when most people refer to multimedia , they generally mean the combination of two or more continuous media , that is , media have to be played during some well - defined timed times interval , usually with the users interaction 然而,当大多数人谈及多媒体时,他们通常是指混合了两种或两种以上连续的媒体,即,媒体可以在一段规定的时间之内连续播放,并且通常伴随着与用户的交互。
Nevertheless , when most people refer to multimedia , they generally mean the combination of two or more continuous media , that is , media have to be played during some well - defined timed times interval , usually with the users interaction 然而,当大多数人谈及多媒体时,他们通常是指混合了两种或两种以上连续的媒体,即,媒体可以在一段规定的时间之内连续播放,并且通常伴随着与用户的交互。
These techniques must be applied to all system resources involved in the continuous media data processing , be applied to all system resources involved . the cpu is just one of these resources - all components must be considered including main memory , storage , i / o devices and networks 操作系统必须将实时调度技术应用于和连续媒体数据处理有关的所有系统资源,即涉及端到端的整个数据路径? ?包括cpu 、主存、存储器、 i / o设备和网络。
It may bring adverse effects on the existing tcp applications ( e - mail , www , and ftp ) and even cause network congestion and ultimately lead to congestion collapse . to tackle these problems , congestion control mechanisms have to be incorporated into continuous media applications 由于现有流媒体应用采用的协议不具备tcp友好的特点,对目前因特网上占主要地位的tcp业务( e - mail 、 www 、 ftp )带来严重影响,导致网络拥塞,甚至发生拥塞崩溃。
From the end - to - end perspective , continuous media applications require good qos support which involves communication latency , transmission bandwidth and data loss ratio etc . however , protocols in current continuous media applications are not tcp - friendly ( there is unfairness among protocols ) 目前因特网上的实时流媒体(视频、音频)应用一直呈快速增长趋势。从端到端的角度考虑,这些应用中的通讯延时、传输带宽和数据丢失等性能指标需要良好的qos支持。