From Chairman Dr. Jack A. Shulman: "One of the best hackers I ever met, believes that the most common weakness on the web is the overdependence upon BIND and it's somewhat gappy design, that could allow system security breaches due to a somewhat thin security system.  I disagree.  The most common weakness on the web is the tendency by anyone has who has experience to believe they have all the answers.  No one does! There's a lot about TCP/IP that is good, even if it has sacrificed layers in the OSI model.  There's a lot about it's current usage that is badly thought out.  It's what we have to work with.  So learn it well and use it well. Here's a few of the tools I use when planning out and implementing a good, secure public network and good, secure private nets. But don't be surprised if along comes some hacker with a new way to breach the premises.  Be on the lookout for that one guy who noticed what you didn't.  No solution is perfect.  But, diligence and flexibility pays off!"