为了进一步提高网络拥塞控制性能,针对基于流体流理论提出的网络流量模型的近似问题,提出了网络流量的精确模型,并且基于该模型把一类PID设计方法用于主动队列管理(AQM)控制器的设计,建立了一种新的拥塞控制算法,采用4σ+ω2+e≤0的抛物线区域作为D稳定域,使得所有的特征根Si位于D稳定域内,利用约束化的数值优化方法寻找控制器参数,以获得预期的动态性能.理论分析和仿真实验表明,该控制算法的综合性能优于RED算法,验证了该算法的有效性.
To improve the performance of network congestion control system, an exact model of network date flow is presented based on fluid flow theory. Based on this new model, a novel PID-like(PID is the abbreviation of Proportional-Integral-Differential) controller design method was applied to Active Queue Management (AQM), and a new network congestion control algorithm was presented. Taking a parabolic region of 4σ- +ω2 +e ≤ 0 as the D-stability region, all characteristic roots were located within the D-stability regions. A numerical optimization algorithm was used to search the controller parameters, and then the desired dynamic performance was achieved. Theoretical analysis and simulated experimental results show that the integrated performance of the proposed algorithm is obviously superior to that of the existing RED algorithm. Which verifies the validity of the proposed method.