大多数无线网络的TCP友好拥塞控制算法都是利用单向时延ROTT的值判断网络状态的,但这种方法ROTT抖动对算法的影响很大,并且无法区分无线误码丢包和拥塞丢包,使得网络吞吐量大大降低,造成发送速率极不稳定.为保证无线网络中多媒体数据的传输质量,本文提出了一种适用于无线网络的流媒体传输的改进TFRC机制,采用方差机制确定网络所处的状态,重新设计适合于无线环境传输的吞吐量模型公式.仿真结果验证了该机制能够获得较高的吞吐量和较平缓的发送速率,并具备较好的TCP友好特征,保证了流媒体服务质量.%Most of TCP friendly congestion control algorithms of the wireless network use the value of one-way delay to determine ROTT network status, but in these algorithms ROTT jitter greatly influences the algorithm and can not distinguish the wireless error packet loss and congestion packet loss. This makes the network throughput significantly reduced, resulting in sending rate highly volatile. In order to ensure multimedia data transmission quality of the wireless network, this paper proposes a suitable wireless network streaming media to improve TFRC mechanism, in which variance mechanism is used to determine the status of the network, and re-design transmission throughput model formula for the wireless environment. The simulation results validate that the mechanism can obtain higher throughput, gentler sending rate and with a better TCP friendly features, and guarantee the streaming quality of service.
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