Firestarter is a firewall tool for Linux, and uses GNOME. You can use the wizard to create a basic firewall, then streamline it further using the dynamic rules.

You can open and close ports with a few clicks, or stealth your services giving access only to a select few.

It features a real-time hit monitor which you can watch as attackers probe your machine for open ports.

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Here are some key features of "Firestarter":

· Open Source software, available free of charge
· User friendly, easy to use, graphical interface
· A wizard walks you through setting up your firewall on your first time
· Suitable for use on desktops, servers and gateways
· Real-time firewall event monitor shows intrusion attempts as they happen
· Enables Internet connection sharing, optionally with DHCP service for the clients
· Allows you to define both inbound and outbound access policy
· Open or stealth ports, shaping your firewalling with just a few mouse clicks
· Enable port forwarding for your local network in just seconds
· Option to whitelist or blacklist traffic
· Real time firewall events view
· View active network connections, including any traffic routed through the firewall
· Advanced Linux kernel tuning features provide protection from flooding, broadcasting and spoofing
· Support for tuning ICMP parameters to stop Denial of Service (DoS) attacks
· Support for tuning ToS parameters to improve services for connected client computers
· Ability to hook up user defined scripts or rulesets before or after firewall activation
· Supports Linux Kernels 2.4 and 2.6
· Translations available for many languages (38 languages as of November 2004)