linux and microcontroller

Vuurmuur is graphical front end for famous firewall software iptables. You can make complex firewall rules in simple steps. Vuurmuur supports traffic shaping, has powerful monitoring features, which allow the administrator to look at the logs, connections and bandwidth usage in realtime.

install in ubuntu (jaunty and later)
$ sudo apt-get install vuurmuur

official site http://www.vuurmuur.org/