This chapter is aimed at getting you started and to help you understand the role Netfilter and iptables play in Linux today. This chapter should hopefully get you set up and finished to go with your experimentation, and installation of your firewall. Given time and perseverance, you'll then get it to perform exactly as you want it to.
The iptables user-space package can be downloaded from the http://www.netfilter.org/documentation/index.html#FAQ - The official Netfilter Frequently Asked Questions. Also a good place to start at when wondering what iptables and Netfilter is about.. The iptables package also makes use of kernel space facilities which can be configured into the kernel during make configure. The necessary steps will be discussed a bit further down in this document.