摘要
当前大多数AQM机制的实现算法都更多地强调了算法的效率和稳定性而忽视了公平性。已有研究表明,TCP的RTT不公平性问题和多拥塞链路环境下的不公平性问题广泛存在于众多的著名AQM实现算法中,比如RED,REM,PI和AVQ等。虽然FRED和Balanced RED可以解决这些不公平性问题,但它们的实现都需要在路由器上保留每流状态信息,算法可扩展性存在问题。在实际网络测量试验结果的基础上,提出了利用IP数据报头中的TTL字段信息来增强公平性的思路,并据此对RED算法进行了扩展,实现了一个公平性增强的RED算法(FERED)。NS2仿真试验结果显示FERED可以显著增强公平性,同时保留了RED算法可以很好地控制队列长度的优点,而且FERED实现简单,无需在路由器保留每流状态信息。
Most of existing AQM schemes focus on the efficiency and stability, but neglect the fairness. Some researches have shown that TCP RTT unfairness and unfairness led by multiple congestion links widely occur in many famous AQM schemes, such as RED, REM, PI, AVQ etc. Although FRED and Balanced RED can solve unfairness problem, both of them keep per-flow state in router. Based on measurement results in real Internet, a fairness enhancement RED, in which TTL field in IP header is used to improve fairness of RED, was proposed. The results in NS2 show that FE- RED improves fairness greatly and inherits the merit of RED to control queue length. Moreover FERED can be implemented simply and no per-flow state is needed in router.
出处
《计算机科学》
CSCD
北大核心
2009年第2期122-124,共3页
Computer Science
基金
西安交通大学“机械制造系统工程国家重点实验室”开放基金资助
