Oscillation and Period Doubling in TCP/Red System: Analysis and Verification
Oscillation and Period Doubling in TCP/Red System: Analysis and Verification
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DOI：
10.1142/s0218127408021105
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发表时间：
2008-05
期刊：
影响因子：
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通讯作者：
X. Chen;Siu‐Chung Wong;C. Tse;F. Lau
中科院分区：
文献类型：
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作者：
X. Chen;Siu‐Chung Wong;C. Tse;F. Lau
已经知道，瓶颈RED（随机早期检测）网关在调节多个相同的TCP（传输控制协议）流时可能变得振荡。然而，这种振荡行为的系统解释是不可用的。在本文中，我们首先使用流体流动模型来推导系统的特征频率，然后与从“ns-2”模拟中观察到的RED队列长度波形的频率进行比较。“ns-2”模拟器是唯一可行的模拟工具，被工业界接受用于验证目的。TCP源频率分布的分析揭示了发生倍周期时，系统进入不稳定区域的滤波器分辨率的变化。由于随机事件和大量的TCP流参与的过程中产生的平均系统动力学，统计的观点是采取的分析。我们的结果反映了真实的系统行为，因为它们是基于“ns-2”模拟的数据，而不是分析模型的数值模拟。振荡的物理机制解释的TCP源频率和TCP-RED系统的特征频率的差异。
It has been known that a bottleneck RED (Random Early Detection) gateway can become oscillatory when regulating multiple identical TCP (Transmission Control Protocol) flows. However, a systematic explanation of such oscillatory behavior is not available. In this paper, we first use the fluid-flow model to derive the system characteristic frequency, and then compare with the frequencies of the RED queue length waveforms observed from "ns-2" simulations. The "ns-2" simulator is the only viable simulation tool accepted by industry for verification purposes. Analysis of the TCP source frequency distribution reveals the occurrence of period doubling when the system enters the instability region as the filter resolution varies. Since random events and a large number of TCP flows are involved in the process of generating the average system dynamics, a statistical viewpoint is taken in the analysis. Our results reflect the true system behavior as they are based on data from "ns-2" simulations rather than numerical simulations of analytical models. The physical mechanism of oscillation is explained in terms of the difference in the TCP source frequency and the TCP-RED system characteristic frequency.