用于视频传输的Ad Hoc网络路由协议优化方法

摘要

In video transmissions over Ad Hoc networks,packet loss rate of the video stream is a key factor affecting the video transmission quality.The traditional AODV routing protocol depends itself solely on such information as the number of hops in RREP messages for routing updates,easily leading to network load imbalance,increasing the packet loss rate of video frames and causing unclear video images.The proposed V-AODV protocol select the routes on the basis of the load status and hop number to avoid heavy load nodes,enabling balanced load in the entire video network.This paper simulates the video stream transmissions under the V-AODV and AODV protocols respectively using NS2 and compares them thereafter.The results indi-cate that V-AODV reduces the packet loss rate of video frames and effectively realizes load balance in video transmissions.%在 Ad Hoc(无线自组织)网络中进行视频传输时,视频流的丢包率是影响视频传输质量的关键参数。传统的 AODV(按需距离矢量)路由协议仅依据 RREP(路由应答)消息中的跳数等信息来进行路由更新,容易导致网络负载不均衡,增大了视频帧的丢包率,造成视频画面不清晰。文章提出的 V-AODV(用于视频传输的按需距离矢量)协议依据 V-RREP(用于视频传输的路由应答)包中负载状态信息和跳数信息来进行路由选择,避开了负载较重的节点,使得整个视频网络负载均衡。通过NS2(网络模拟器)分别对 V-AODV和 AODV协议下的视频流传输进行了仿真对比,结果表明,V-AODV 协议降低了视频帧的丢失率,有效地解决了视频传输中的负载均衡问题。