Implement Port-Knocking Security with knockd

Instead of closing ports, make them disappear.

Port knocking can't be the only security weapon in your arsenal, but it helps add an extra barrier to your machine and makes it harder for hackers to get a toehold into your system.

Federico Kereki is an Uruguayan Systems Engineer, with more than 20 years' experience teaching at universities, doing development and consulting work, and writing articles and course material. He has been using Linux for many years now, having installed it at several different companies. He is particularly interested in the better security and performance of Linux boxes.