Traffic Control Technology Research Based On Netfilter Framework

With the rapid development of Internet technology and various network services, more and more network problems increasingly arise. For example, large of P2 P businesses make great impact on traditional network businesses and hinder users’ cyberspace experience. Guided by the principle of "convenient and easy to use, high cost performance", this paper is committed to improving the quality of network service and offer Internet users better service with limited bandwidth. Based on thorough study of traffic identification and control for Linux operation system, this paper designs and implements a network traffic control prototype system based on Netfilter framework. In testing environment, it proves that the traffic control prototype system can improve the quality of network service for small and medium enterprises. The main work in this paper is as follows:Firstly, this paper studies the principle and working mechanism of kernel network processing model in Netfilter framework, and further puts forward a traffic control prototype system model and design scheme based on Netfilter framework of Linux operation system on this basis.Secondly, this paper selects forward chain based on Mangle table as data packets marking method for traffic control system, which correctly identifies and marks the transferring data packets in and out of traffic control system.Thirdly, based on HTB which is an original queuing algorithm of Linux kernel traffic control, this paper designs HTB+SFQ queuing algorithm with four-layer tree mechanism, which controls effectively the assured bandwidth, largest bandwidth and borrowed bandwidth for different users and businesses, but also avoids the continuing occupation of single connect within an internal network service.Fourthly, based on Linux operation system 2.6.32 kernel and X86-64 hardware platform, this paper implements the traffic control prototype system of GTK+/Glade graphic interface with designed function modules and control strategy.Finally, through the function and performance testings for the traffic control prototype system, it is verified the correctness and effectiveness of the system.This traffic control prototype system implements all functions by open source softwares, which makes sure the system with better portability and expansibility.