This article will be my first in a series of articles about network security. I decided to write this article about iptables while it is still fresh from my memory. This is intended for beginners who wish to get familiar with the basics of Iptables(like me) and some basic concepts in creating a network firewall.
What is Iptables?
Iptables is a program in Linux that is used to setup, maintain and inspect IPv4 packet filter rules. For IPv6 traffic, there is also an Ip6tables program that can be used to inspect IPv6 packet filter rules. Since IPv4 address is already almost depleted, I find it very important to give examples in both IPv4 and IPv6 packet filtering.