Open source and free under the GNU General Public License (GPL)
Easily blocks sessions based on simple rules
Rules can be based on a variety of attributes
The firewall is the most basic security element to hide your network from the outside and control all external access points (also known as ports). It lets you block unwanted activity and protect your network. You can build a list of rules that meets your unique needs - control traffic by protocol, port, IP and more, as well as set a default action for when no existing rules match. Firewall evaluates traffic traveling across your network by applying your rules until a block/pass verdict is reached or a default action is taken.