How to Scan the Open Ports Through Firewall using Fscan

• The Fscan application is a tool from Foundstone that allows an attacker to scan for open ports on targets.
• A unique feature of Fscan is that it allows an attacker to scan in a random, “quiet” mode to try to circumvent Intrusion Detection Software (IDS).
• Fscan also allows the scan to be bound to a specific port—for example, port 80, which most firewalls allow. (This would be the –i option.)

From a DOS prompt type the following with the syntax of:

fscan (IP Address or Name) (Port #)