"In the first two parts of this series we took a tour of the Soekris 4521 single-board computer and installed the Pyramid Linux operating system. Now it's time to build a good stout iptables firewall.
"When you're used to hacking on old PCs it's easy to fall into bad habits, like stuffing all manner of services on border routers and turning them into 'Internet gateway/LAN servers' because you have the capacity, and you don't want to clutter up the place with big old PCs dedicated to specialized jobs. But this isn't really the best way to design your network. Putting a router and a firewall on a single device makes sense for us ordinary mortals with simple routing needs and not-too complex firewalling schemes. Put the intrusion-detection/proxies/Web/mail/FTP/file/etc. servers somewhere else..."
