"reaffirm" - 1 õppematerjal

TheCodeBreakers

between different army chiefs for an unlimited time," he wrote. In that one sentence, Kerckhoffs differentiates pre-telegraphy military communications from post-. The sentence is pregnant with most of the requirements that have come to be demanded of systems of military cryptography, requirements such as simplicity, reliability, rapidity, and so on. This clear recognition of the new order constitutes Kerckhoffs' first great contribution to cryptology. The second was to reaffirm in a modern context the principle that only cryptanalysts can know the security of a cipher system. It is the form of judgment which is still used. From these two fundamental principles for selecting usable field ciphers, Kerckhoffs deduced six specific requirements: (1) the system should be, if not theoretically unbreakable, unbreakable in practice; (2) compromise of the system should not inconvenience the correspondents;