【作者】 丁大为； 朱杰； 罗晓曙； 郑渊博；

【Author】 Dawei Ding , Jie Zhu , Xiaoshu Luo, Yuanbo Zheng ( Department of Electronic Engineering, Shanghai Jiao Tong University, Shanghai 200240, China) ( School of Electronic Science and Technology, Anhui University, Hefei 230039, China) ( Department of Physics and Electronic Science, Guangxi Normal University Guilin 541004, China)

【机构】 上海交通大学电子工程系； 广西师范大学物理与电子科学学院；

【摘要】 近年来,随着互联网的规模和用户数量的不断增长,它在我们的生活和现代社会中扮演了越来越重要的角色。然而,未受控制的网络将导致严重的拥塞,因此拥塞控制成为越来越重要的问题。整个网络拥塞和避免机制是由用户终端的点到点传输控制协议(TCP)拥塞控制机制以及路由器端的队列管理机制构成。本文首先介绍一种随机早期检测机制(RED)与混合TCP和UDP流的离散时间模型。我们用这种一阶离散映射模型来解释系统的不稳定性、分岔和混沌行为。时间延迟反馈控制方法的主要优点是它不需要对应于所需不稳定点的参考信号。因此,我们使用标准时间延迟反馈控制和扩展时间延迟反馈控制方法来稳定系统平均队列长度的混沌行为。从数值模拟结果我们可以得出, 当选择合适的反馈参数,我们可以将混沌轨道稳定到一个不动点。更多还原

【Abstract】 With the rapid growth of the Internet both in its size and the number of subscribers over the last decade, it plays an ever-increasing role in our life and the modern human society. However, an unadjusted network may suffer from severe congestion and the problem of congestion control is emerging as a more crucial problem. The whole Internet congestion and avoidance mechanism is a combination of the end-to-end Transmission Control Protocol (TCP) congestion control mechanism at the end hosts and the queue management mechanism at the routers. In this paper, we first introduce a discrete time model of the mixed TCP and User Datagram Protocol (UDP) connection with the RED mechanism. We use this one order discrete time map model to explain the instability, bifurcation and chaotic behaviors of the system. The main advantage of the TDFC method is that it does not require a reference signal corresponding to a desired unstable fixed point. Therefore we use standard time delayed feedback control and extended time delayed feedback control approaches to control the system parameter in order to stabilize the chaotic behavior of average queue size of the system. From numerical simulation we conclude that the chaotic orbit can be stabilize to a fixed point when we choose proper feedback parameters.更多还原