一种有线-无线异构网络的媒体感知ARQ控制方案

在基于IEEE802.11b协议的无线局域网(WLAN)中,针对MPEG4视频数据在有线-无线异构网络中最后一跳的传输,当无线网络出现较严重的拥塞和干扰情况下,会导致视频播放的图像质量下降。提出了一种基于路由代理的媒体感知ARQ(automatic repeat request)机制,该机制通过利用路由代理接收视频信息并将该信息反馈给无线接入点(AP)以实现选择性的视频数据包的重传,并根据时延要求进行优先数据包重传以保障时延的要求,提高异构IP网络的视频播放质量和用户感受质量。仿真结果表明,本算法对无线链路的丢包和队列拥塞丢包进行了保护,可以提高视频的播放质量。

A Novel Media-aware ARQ Algorithm for Wired/Wireless Hybrid IP Networks

For wired-wireless heterogeneous networks involving IEEE802.11b based WLAN,if serious congestion and interference occur in the wireless network,the last hop transmission of MPEG4 video data will deteriorate the quality of video playout.To tackle this problem,a media-aware ARQ mechanism is proposed based on routing proxy.The mechanism realizes selective retransmission of video data packets by use of routing proxy to receive video information and feedback it to the wireless access point(AP).The retransmission is with priority according to the delay requirement to enhance the video playout quality and user’s quality of experience.Simulation results have shown that the proposed mechanism can protect the network from the packet loss due to wireless link and/or queuing congestion and thus improve the quality of video playout.