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An Introduction to the Shorewall Firewall Tool

Linux is well known for being a highly secure platform. One of the reasons for said security is the Netfilter system. For those that don’t know, Netfilter is a framework, provided by the Linux kernel, that allows for various networking operations, such as packet filtering, network address translations, port translation, and the ability to block packets from reaching specific locations. For most distributions, Netfilter is implemented through the user-space application, iptables. Although many would agree that iptables is the most powerful security tool you can work with, along with that power comes a level of complexity that stumps many an IT administrator.