Network Congestion Control Of PID Algorithm

Nowadays,with the development of communication technology,the congestion problem of the network is more and more serious.This problem becomes the biggest bottleneck restricting the development of the network.The root cause of congestion is that the load provided by the user to the network far exceeds the network's own capacity and processing power.In the process of data transmission,congestion will lead to the significant decrease in overall network performance and the robustness,and even the serious collapse of the whole network.Therefore,the congestion control algorithm of the network is proposed to alleviate Congestion problem.Congestion control is generally based on queue management and route routing,and its ultimate goal is to optimize the use of network resources.In this paper,the congestion control algorithm is mainly studied in the following aspects:Firstly,the three typical queue management algorithms are analyzed.Drop Tail algorithm as a typical passive queue management algorithm,although the method is simple,there is a very easy to produce global oscillation shortcomings.RED and PI as the basic active queue management algorithm,the network performance has improved,but the RED algorithm is sensitive to parameter settings,and can not effectively control the queue length under heavy load,PI algorithm can be under the load of the queue length control,but the control effect is not ideal.Secondly,the active queue management algorithm is further studied.Taking into account the nonlinear characteristics of the network system,the TCP network dynamic model is established and linearized as the basis of the PID algorithm.PID algorithm based on the PI algorithm to add the differential control,effectively improve the dynamic performance of the system,according to the network input deviation ratio,integration,differentiation to control,manage the cache queue length,so that data delivery as fast and reliable as possible..Finally,by improving the trend of the queue error,the PID algorithm is improved and added more detail control rules.The corresponding adjustment is made under different data conditions,so that the distribution and processing of the packet will be faster and more accurate.The network simulation platform is built by NS2 software under Linux system,and the different schemes are experimented separately.The simulated statistical parameters are compared and analyzed.