Ask Fyodor Your Network Security Questions

Fyodor is the driving force behind Insecure.org and the top-rated Nmap network exploration and security auditing tool. He's also involved in The Honeynet Project (and is a coauthor of the project's book, Honeynet: Revealing the Security Tools, Tactics, and Motives of the Blackhat Community). One question per post, please. We'll run Fyodor's answers to 10 of the highest-moderated questions as soon as he gets them back to us.