中文摘要：

定量分析了FAST/RED系统在平衡态时链路队列长度、系统稳定性与RED控制器参数关系.针对FAST协议发现链路丢包就会采用激进的窗口减半策略造成网络不稳定的缺陷,根据稳定性分析提出一种充分利用源端能够获得的排队时延和丢包频率的历史变化信息,协同合作探测网络的拥塞状况,改进FAST协议源端窗口调整策略,从而间接修改RED控制器参数,提高了系统的稳定性.NS-2仿真验证了稳定性理论分析的准确性和改进策略的有效性.

英文摘要：

The relations among equilibrium＇s queue length,the stability of fast access storage technology/random early detection （FAST/RED） system and the RED parameter were analyzed quantitatively.Aimed at the weakness of FAST that adopted radical window halving strategy once a packet was detected to be lost,the network congestion state was cooperatively detected by making full use of the history information about the queue delay and the losing packet frequency,based on this stability analysis an enhanced FAST protocol window adjustment strategy was proposed according to this congestion state,which equals to adjust RED parameter indirectly and improve the stability of FAST/RED system.NS-2 simulation results were presented to verify the exactness of this stability analysis and the effectiveness of this enhanced method.