I. Several tools automate the remote discovery of firewall rules and assist an administrator in analyzing the rules to determine exactly what they allow and what they reject.
II. Emphasize that administrators who feel wary of using the same tools that attackers use should remember:
• Regardless of the tool that is used to validate or analyze a firewall’s configuration, it is the intent of the user that will dictate how the information gathered will be used.
• In order to defend a computer or network well, it is necessary to understand the ways it can be attacked.
• Thus, a tool that can help close up an open or poorly configured firewall will help the network defender minimize the risk from attack.