The following is a brief guide to using the Kde firewall tool Guarddog to set up a Firewall suitable for home use on Debian.
Read the blog here
GNU/Linux like other Operating Systems has a firewall. The main difference between the GNU/Linux firewall and the Windows firewall is that the firewall on GNU/Linux is built directly into the kernel and is called Iptables. This means that it does not use systems resources like a Windows firewall would e.g. Norton Firewall. Because of this there are a number of distributions whos sole aim is to act as a firewall. This basically means you can turn your home computer into Firewall/Router and then have other computers connect to the network through it. For example the following distributions are all designed to act as nothing more then Firewalls; Smoothwall, IPCop and Trustix.