Lokkit is an attempt to provide firewalling for the average Linux end-user. Instead of the user having to configure firewall rules, the Lokkit program asks a small number of simple questions and writes a firewall rule-set for you.
Note: Lokkit is not designed to configure arbitrary firewalls. To make it simple to understand it is designed solely to handle typical dial-up user and cable modem setups. It is not the answer to a complex firewall configuration, and it is not the equal of an expert firewall designer.
Lokkit will walk you through a set of choices for your firewall. At any stage you can go back and alter your earlier settings. At the end you can accept or reject the settings.