How To Use fwknop to Enable Single Packet Authentication on Ubuntu 12.04
Single Packet Authentication is a method that grew out of earlier port knocking as a way of keeping services shielded until you request access through a predefined sequence of events. Single packet authentication does this by sending a single encrypted packet to the server in order, which can then validate the client and open the requested port. In this article, we will discuss how to use the fwknop suite to implement single packet authentication on an Ubuntu 12.04 VPS.