Research On The Technologies Of Network Traffic Control And Shaping

With the rapid development of Internet applications, there are more and more problems brought up in network systems. The most urgent one of these problems is the network performance reduction due to ineffective management of network bandwidth resources. Different resources occupation of network applications usually bring about the situation that non-critical network applications cosume most of the bandwidth, which seriously impact on the transmission quality of key network applications. At present, one of the main research ccontents of network traffic control is to research how to control network traffic effectively and ensure that the key network applications run normally while non-critical applications restrained.At present, the simple control method in network traffic control model cannot satisfy user's control requirement. Based on analyzing the disadvantages of network traffic model, this paper studied the method of control combination, and focused on how to load control strategies dynamically with user's control requirement. In ordor to design network traffic model and system, this paper analysed network traffic control mechanism based on the network principle. The main works done in this dissertation are as the following:â‘ The causes of network congestion are analyzed. Then the relationship between TCP congestion control and traffic control is researched in theory. The TCP traffic control mechanisms are specially analyzed, including TCP slide window, retransmission and self-synchronization mechanism etc. As a result, we find that it is feasible to control network traffic in real network environment.â‘¡Some network traffic control models are studied over edge gateways. A new model based on user strategy is proposed: adding strategy tree to load user control strategies dynamically in traditional network traffic control model. The user-defined control strategies ensured that critical network applications run normally while non-critical applications restrained.â‘¢A prototype system of network traffic control model based on user strategy is designed and implemented on netfilter framework in Linux kernel 2.6. With the configured transparent bridge and Apache server, the prototype system implemented visualized control management using CGI extend programme. Finally, experiments are conducted to test the prototype system. The results reveal that the prototype system can correctly and effectively control network traffic.