Could someone point to a contest where an attacker has managed to bypass port knocking. Surely someone has tested its effectiveness at creating more work for a

Could someone point to a contest where an attacker has managed to bypass port knocking. Surely someone has tested its effectiveness at creating more work for attackers. How can anyone measure the effectiveness of the advice given by a security consultant? It saved a client from disasters that did not happen? How can anyone prove that such disasters would have happened? Answer: Proof of concept. To question the effectiveness of port knocking, one needs some real stories of real disasters where port knocking was being relied on. Proof of concept. Otherwise all the discussion is still just speculation.