Firestarter: Fast firewalls made simple
Source: Linux Beginner.org
Firestarter is a graphical based firewall interface to the ipchains/Netfilter (iptables) firewalls that come with your Linux distribution, ipchains is used mostly for 2.2.x kernels and Netfilter is used on 2.4.x kernels. This little firewall is easy to use and packs quite a punch, it handles masquerading for multihomed machines (two or more network adapters,) you can change rules, and add dynamic rules on the fly.
