关键词: 主动队列管理, 缓存, 队列, 服务质量, 时延

Abstract:

To solve the problem that the queue delay cannot meet the demand of media applications, such as VoIP, real time video and remote video conference in the existing Active Queue Management (AQM) algorithms, a new AQM algorithm named DCQA (Direct Control Queue Delay Algorithm) was proposed. In this new algorithm, to control the queue delay below the expected value, identifying the packet dropping and other corresponding processes were done before a new packet entered the router buffer. The packet dropping rate was computed by PID controller. Then, a simulation in three network environments was conducted to compare the algorithm performance of DCQA and CoDel algorithm. The experimental results show that the queue delay can be effectively controlled and high utilization of link is obtained in DCQA. The detailed data of utilization of link are 99.93%, 99.88% and 99.95%. At the same time, the simulation results show that the probabilities of the queue delay below the expected value are 50.45%, 51.59% and 52.4%, improved by 3.6%, 40.53% and 50.69% compared with the CoDel algorithm. Therefore, DCAQ is applicable for streaming media transmission.

Key words: Active Queue Management (AQM), buffer, queue, Quality of Service (QoS), delay