针对TCP(Transmission Control Protocol,传输控制协议)网络中的拥塞控制问题,提出了一种滑模拥塞控制策略。基于TCP网络拥塞控制模型,利用线性矩阵不等式设计了一个渐近稳定的滑模面,该滑模面能够补偿TCP网络中的不确定性因素的影响。...针对TCP(Transmission Control Protocol,传输控制协议)网络中的拥塞控制问题,提出了一种滑模拥塞控制策略。基于TCP网络拥塞控制模型,利用线性矩阵不等式设计了一个渐近稳定的滑模面,该滑模面能够补偿TCP网络中的不确定性因素的影响。另外,为了减小路由器中队列长度的振荡,提出了一种改进的到达条件。多种情况下的仿真实验表明,所提出的控制策略与普通的滑模拥塞控制策略相比具有更好的稳定性和鲁棒性。展开更多
针对TCP(Transmission Control Protocol,传输控制协议)网络的拥塞控制问题,基于T-S(Takagi-Sugeno)模糊模型,采用滑模控制理论提出了一种新的AQM(Active Queue Management,主动队列管理)算法。考虑到TCP网络中存在的不确定和时变时滞因...针对TCP(Transmission Control Protocol,传输控制协议)网络的拥塞控制问题,基于T-S(Takagi-Sugeno)模糊模型,采用滑模控制理论提出了一种新的AQM(Active Queue Management,主动队列管理)算法。考虑到TCP网络中存在的不确定和时变时滞因素,首先利用T-S模糊模型对网络进行建模,然后利用线性矩阵不等式设计了一个渐近稳定的滑模面,而且还给出了一种能够明显减小滑模面附近抖振的趋近律,基于该趋近律设计的控制律能够有效地抑制路由器中队列长度的振荡,并使其快速收敛于期望值。仿真结果表明,该算法与普通的滑模控制算法相比具有更好的稳定性和鲁棒性,能够很好地适应复杂多变的TCP网络环境。展开更多
In this paper, the authors investigate the overload problem of a congested router in TCP (Transmission Control Protocol) networks, with a design of an AQM (Active Queue Management) controller based on control theo...In this paper, the authors investigate the overload problem of a congested router in TCP (Transmission Control Protocol) networks, with a design of an AQM (Active Queue Management) controller based on control theory. The model of TCP/AQM is converted into a second-order system with time delay, the stability of the closed-loop AQM system is described in terms of a characteristic quasi-polynomial. The authors focus on the synthesis of first-order AQM controller. The authors' approach consists of determining the stabilizing regions in the parameter space of the first-order controller, then choosing controller's parameters within these regions. Finally, the authors illustrate the proposed methodology with an example and simulations using NS-2 simulator.展开更多
文摘针对TCP(Transmission Control Protocol,传输控制协议)网络中的拥塞控制问题,提出了一种滑模拥塞控制策略。基于TCP网络拥塞控制模型,利用线性矩阵不等式设计了一个渐近稳定的滑模面,该滑模面能够补偿TCP网络中的不确定性因素的影响。另外,为了减小路由器中队列长度的振荡,提出了一种改进的到达条件。多种情况下的仿真实验表明,所提出的控制策略与普通的滑模拥塞控制策略相比具有更好的稳定性和鲁棒性。
基金国家自然科学基金(the National Natural Science Foundation of China under Grant No.60474029)中南林业科技大学青年科学研究基金(the Youth Science Research Foundation of Central South University of Forestry and Technology No.101-0582)中南林业科技大学教学研究基金(the Teaching Research Foundation of Central South University of Forestry and Technology No(.[2004]28-67))
文摘针对TCP(Transmission Control Protocol,传输控制协议)网络的拥塞控制问题,基于T-S(Takagi-Sugeno)模糊模型,采用滑模控制理论提出了一种新的AQM(Active Queue Management,主动队列管理)算法。考虑到TCP网络中存在的不确定和时变时滞因素,首先利用T-S模糊模型对网络进行建模,然后利用线性矩阵不等式设计了一个渐近稳定的滑模面,而且还给出了一种能够明显减小滑模面附近抖振的趋近律,基于该趋近律设计的控制律能够有效地抑制路由器中队列长度的振荡,并使其快速收敛于期望值。仿真结果表明,该算法与普通的滑模控制算法相比具有更好的稳定性和鲁棒性,能够很好地适应复杂多变的TCP网络环境。
文摘In this paper, the authors investigate the overload problem of a congested router in TCP (Transmission Control Protocol) networks, with a design of an AQM (Active Queue Management) controller based on control theory. The model of TCP/AQM is converted into a second-order system with time delay, the stability of the closed-loop AQM system is described in terms of a characteristic quasi-polynomial. The authors focus on the synthesis of first-order AQM controller. The authors' approach consists of determining the stabilizing regions in the parameter space of the first-order controller, then choosing controller's parameters within these regions. Finally, the authors illustrate the proposed methodology with an example and simulations using NS-2 simulator.