【摘要】 通过对多媒体组播协议的研究,发现在组播树中的路由节点发生故障后,树中节点将分散为若干个不同QoS需求的子树,通常的做法是将子树的所有节点重新发起构造成新的组播树.通过增加对子树受限QoS信息的描述,在组播树中路由节点发生故障之后,只是按照子树的QoS信息重新构造新组播树,子树构造不成功时才进行所有节点的构造.仿真试验表明,在路由节点故障情况下子树的构造成功率平均超过80%,同时这种方可缩短组播树故障恢复时间并降低重构开销.该算法还可以提高组播应用的可靠性.更多还原

【Abstract】 It is found that multicast tree will be divided into some subtrees with different QoS demands after a routing node in the multicast tree goes wrong.Usual treatment method is that all the nodes in the subtrees of the node at fault are used for reconstructing a new multicast tree.In this paper,an algorithm is proposed,by which the subtrees can fast be connected into a new multicast tree according to the QoS information of the subtrees after a routing node goes wrong at fault.Only if this connection fails,are all the nodes in the subtrees used for reconstructing the new multicast tree.The results of the simulation tests show that the success ratio of this connection can be higher than 80%.In addition,the algorithm can shorten the recovery time of the multicast tree and decrease the expense of recovering the multicast tree.It can increase the reliability of the system as well.更多还原