Linux.com: "Firewall Builder (fwbuilder) is a graphical application that can help you to configure IP traffic filtering.

It can compile the filtering policy you define into many specifications, including iptables and various languages used by Cisco and Linksys routers.

Separating the actual policy you define and the implementation in this way should let you change what hardware is running your firewall without having to redefine your policy for that platform."