一种基于MANET的多播协议的设计与实现

Design and implementation of multicast protocol for MANET

传统的应用于有线网络的多播方法很难适应MANET所具有的拓扑结构变化和带宽有限等特点,无法有效地应用于MANET。提出了采用按需路由发现策略的MANET多播路由协议MFGRP。在MFGRP协议中不需要维护全局的路由信息,通过按需路由发现过程,动态更新路由信息和建立网格。多播数据包在转发组成员间进行有限泛洪,使协议能够降低带宽的占用及减少路由更新信息的传播。模拟实验显示协议在带宽较低、多播组成员数量变化较大的移动分组无线网环境中,具有较好的可靠性和工作效率。

The traditional multicast methods proposed for wired infrastructures are not well suited to handle bandwidth limitations and unpredictable topology changes. A multicast protocol, MFGRP, utilizing on-demand routing strategy for MANET is presented. The protocol does not maintain permanent route tables with full topological views. Instead, it applies on-demand procedures to dynamically discover routes and build multicast forwarding grid. The multicast packets are propagated by each forwarding group member via scoped flooding, so the protocol can reduce network bandwidth overhead and avoid the propagation of potentially large routing updates throughout the network. Simulation results show that MFGRP is robust to mobility, has low bandwidth overhead, scales well with membership group size, and can be used effectively for MANET.