Configration And Analysis Of Netfilter/Iptables In Linux Kernel

With the increasingly serious network security problem, firewall has been payedmore and more attention.As the Linux operating system source code is open, Linuxsupplies a good platform for the research of firewall technology.To begin with, network security problem and the concept of firewall are given inthis paper. Then the key technology of firewall is introduced. What’s more, this paperalso introduces the Netfilter framework based on the Linux kernel and the iptables tooland analyzes the processing of Netfilter/iptables framework for packet.Based on the analysis of a WiMAX product, a new kind of firewall, whichcoincides with the characteristics of the WiMAX product is presented at the end of thispaper. Then a comparation of using scripting language and C language to config thefirewall has been made based on analyzing the cooperative work principle of firewalland other modules. According to the results of comparing and analyzing, this paperchoose C language to give the program module of key technology of firewall (statedetection technology, NAT, etc); The analysis of testing result shows that the keytechnology implemented by C language meets the design requirements.The above configuration of firewall based on WiMAX is implemented o n Linuxembedded platform. The firewall is suitable for the development of other network withthe port between a server and client that using CGI standard as user managementinterface and using the language Javascript as the develop language.