移动应用层组播中基于父节点备份机制的快速重定向策略研究

A quick redirection strategy based on parent node backup mechanism in mobile ALM environment

针对移动环境下应用层组播节点的高度动态性问题,提出了一种基于设施的移动环境下组播系统故障恢复策略。该策略利用所提出的主动故障恢复方案以及备份父节点重定向算法,达到快速重定向的目的。还提出利用组播树的相似度来衡量重定向算法对组播拓扑变化的影响,从而判断重定向策略的好坏。实验仿真结果表明,所提出的快速重定向策略具有时延低的优势,并且重定向后对组播拓扑变化影响较小。

To address solving the high dynamics problem of mobile Application Layer Multicast （ALM） nodes,a multicast system＇s failure recovery strategy in the mobile environment is proposed.This strategy can achieve the goal of quick redirection by using active failure recovery method and the proposed redirection algorithm based on parent node backup.Besides,we propose to use the similarity of multicast tree to measure the impact of the redirection algorithm on the change of multicast system＇s topology,thus evaluating the quick redirection strategy.Simulation experiment is given to show that the proposed quick redirection strategy has low delay and small influence on the multicast system＇s topology..