基于TCP友好的无线网络拥塞控制机制研究

网络实时多媒体业务的广泛应用对传统传输层协议提出了新的挑战:拥塞控制机制的缺乏使得UDP严重抢占TCP应用的共享带宽,从而降低网络的公平性,甚至导致网络拥塞.针对无线网络的高误码特性,将传输延时抖动引入到TFRC控制机制中,提出了一种基于速率控制的TCP友好拥塞控制算法TFRC-JI.该算法基于传输延时抖动有效区分无线链路的拥塞和误码,并以此反馈至发送端,实现不同的速率控制机制.实验结果表明,与传统的TFRC相比,改进的TFRC-JI在保持对TCP业务友好性的同时实现了链路的高效使用,并降低了传输时延抖动,从而较好地适应多协议共存的无线网络实时业务传输.

Research of TCP-friendly Congestion Control Protocol in Wireless Network

The network real-time multimedia service's widespread application presented an new challenge to the traditional transport protocol: the deficiency of congestion control mechanism causes UDP to seriously seize the sharing band width of the TCP application, thus reduces the network fairness, even causes network congestion. Based on the characteristic of high error rato in wireless network, a novel TCP friendly congestion control algorithm TFRC-JI was presented in this article, which introduces the latency vibration to distinguish the link congestion from code error, thus different speed control mechanism is feedback to the transmitting end. Simulation experiment result indicated that compared with the traditional TFRC mechanism,the throughput of wireless link is enhanced while TCP friendly also maintaines using TFRC-JI,which suites well for real-time service transmission.