Hark! Who Goes There?- Gaining Network Access By Knowing The Secret "Port Knock"

Kids often develop a secret knock to get into the neighborhood clubhouse- two knocks, a long pause, 1 knock,a short pause and then 3 quick knocks- voila! You're in!! Network administrators and malware authors are now using a similar concept to open holes in the firewall and allow connections from remote devices outside of the firewall. To learn more about the concept of Port Knocking and how it can help you or be used against you, click here: Port Knocking.