Kerckhoffs's principle (also called Kerckhoffs's desideratum, assumption, axiom, doctrine or law) of cryptography was stated by Netherlands born cryptographer Auguste Kerckhoffs in the 19th century: A cryptosystem should be secure even if everything about the system, except the key, is public knowledge.
I’m a firewall engineer dedicated to tracking bots, scanners, and other suspicious activity on the web. I maintain an alternative IP list (below) that offers a complementary approach to most commonly available lists out here on the internets.