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在高速分组交换环境中 ,提出了构造多信道广播树 ,且满足实时交互性应用端到端变化要求的总延误问题。多信道广播路由将寻找从源到包括所有多信道广播终端的一棵有根树。在多媒体应用中 ,关于路由问题有两种要求 :最小总延误和延迟变化。在实践中链路延迟和终端延迟的概念是有区别的。重新定义延迟的概念 ,也就是端到端的路径延迟定义为截止延迟或界定延迟 ,延误成员数的延迟定义为松驰延迟。终端的松驰延迟具有的特征是沿着一棵树从源到任何一个终端的累积延迟可以超过松驰延迟的值。确定这样一棵约束树的问题是 NP-完全的。由时间的复杂性和动态成员的灵活性 ,提出了一个有效的启发式算法。
In high-speed packet switched environment, a total delay problem of constructing multi-channel broadcast tree and meeting the requirement of end-to-end change of real-time interactive applications is proposed. Multicast routing will look for a rooted tree from the source to include all multicast channels. In multimedia applications, there are two requirements for routing issues: the smallest total delay and the delay variation. In practice the concept of link delay and terminal delay is different. The concept of redefinition of delay, that is, an end-to-end path delay is defined as a cut-off delay or a defined delay, and a delay of delay membership is defined as slack delay. The relaxation delay of a terminal has the characteristic that the cumulative delay along a tree from source to any one terminal can exceed the value of relaxation delay. The problem of determining such a constraint tree is NP-complete. By the complexity of time and the flexibility of dynamic members, an effective heuristic algorithm is proposed.