基于关键节点时延约束低代价组播路由算法

摘要

This paper proposed a delay-contrained and low-cost multicast routing algorithm based on key node according to the construction of delay-constrained and low-cost multicast tree. This algorithm not only improved the existing path selection function which was appropriate for dynamic delay optimization, but also in conception and frequency of key node. Because key node could reduce the time complexity of choosing low-cost path in the first time to choose destination nodes. And then it used the improved path selection function to choose nodes add into the muticast tree one by one. By this way, the multicast tree which met the requirements could be constructed. The simulation results show that this algorithm can not only construct a multicast tree correctly but also need less time than those of many other multicast algorithms.%针对时延约束下低代价组播树的构建方法,提出了一种基于关键节点的时延约束低代价组播路由算法.该算法对已有的动态时延优化的链路选择函数进行改进,并加入关键节点和关键次数的概念.在首次选择目的节点时,重点考虑关键节点和关键次数因素,降低了选择低代价链路的时间复杂性,再利用改进后的链路选择函数依次选择节点加入树中,进而产生满足要求的组播树.实验仿真结果表明,该算法不仅能正确构建出时延约束低代价组播树,且与其他算法相比,构成组播树所需平均时间更少.