适合多源组播的改进型ODMRP

An Improved ODMRP Used for Multi-Source Group Communication

为解决按需组播路由协议(ODMRP)在多源组播应用时开销较大的问题,提出一种仅由转发节点和后备节点参与的改进型路由维护机制.该机制借鉴后备路径的概念,利用无线信道的广播特性和ODMRP周期维护的特点,限制了路由维护时的分组泛洪范围.仿真结果表明,该机制尤其适合于群组中组播源个数较多以及接收成员个数与网络规模之比较小的情况,能有效减少控制分组发送次数,显著提高多源组播发送的分组递交率(PDR).

In order to reduce great overhead of on-demand multicast routing protocol （ODMRP） in multi-source applications, an improved flooding limitation mechanism is presented, which permits forwarding nodes and backup nodes to transmit maintenance packets only. It makes good use of broadcast characteristic of wireless channel and periodical routing maintenance of ODMRP. Simulation shows that this improved ODMRP is especially fit for multi-source group communication and less receiver occasion compared to the network scale. Under the above conditions, the protocol reduces maintenance overhead effectively and enhances packet delivery ratio（PDR） distinctly.