| A firewall is simply another node on your network. Firewalls such as Cisco PIX and Checkpoint Firewall1 maintain a stronger security presence, but each operates in its own unique manner. Hackers learn about your rulesets, firewalls, and their versions through the use of the following: port scanning banner grabbing firewalking To help minimize this danger, firewalls need to be maintained and patched just like any other node on your network.