Linux Iptables Firewall

What is a Firewall: is basically a system that prevents unauthorized communication.
– to it (INPUT)
– from it (OUTPUT)
– through it (FORWARD)

In linux “iptables” performs the functions of the firewall. The main advantages of “iptables” firewall is

– Open Source
– Low Cost (or you can say no cost at all)
– Highly Flexible Stateful Firewall

To properly understand “firewalls”, we will be discussing several different scenarios. Implementing “iptables” is not very difficult but at same time, we would say it is neither easy. You will be able to appreciate the power of linux based firewalls after going through different examples.

We will be covering following topics

– Setting up linux box as a Router

– Blocking Ping

– Blocking Ports

– Save/Restore Rules

– Using “INPUT” Chain

– Using “OUTPUT” Chain

– Using “FORWARD” Chain

– Using “PREROUTING” Chain

– Using “POSTROUTING” Chain

– Various Options, Switches & Actions

– Control Traffic by Mac Address

– Directional Filtering

– Connection Tracking

– Custom Chains

– Transparent Proxy

– IPv6 & Ip6tables

– DMZ (De Militarized Zone)

Linux IPTABLES Firewall Tutorial Download