固定组成员的应用层组播树不稳定问题

Instability Problem of ALM Tree with Stable Members

传统的组播树稳定性研究一般都是基于组播成员的动态变化的.但在应用层组播中,由于组播树的组成节点是应用层的端系统节点,组播成员可以通过欺骗以企图在组播树上占据更有利的位置,从而在组播成员不变时也会造成组播树的不稳定.本文建立了应用层组播节点的欺骗模型,并讨论了在固定组成员的情况下,节点欺骗引起的组播树不稳定问题.模拟实验结果表明,节点欺骗对应用层组播树的稳定性有极大的负面影响.

Traditional researches on the stability of multicast tree mainly focuses on the dynamic change of multicast members. But in application level multicast （ALM）, where the multicast tree is constructed on end systems in the application layer, multicast members can cheat in order to improve their positions in the multicast tree, which may result in the instability of multicast tree even with stable members. This paper establishes the cheating model of ALM nodes, and discusses the instability problem of ALM tree on the occurrence of node cheating when there is no multicast member changing. The simulation results show that node cheating will bring considerable neglect impact on the stability of AIM tree.