The Germans therefore took the clever step of using the day key settings to transmit a new message key for each message.
Impenetrability of the Navajo code was all down to the fact that Navajo belongs to the Na-Dene family of languages, which has no link with any Asian or European language.
Half of them at random will be blocked, and half will pass through, and those that do pass through will be reoriented with a vertical polarization.
They called the Navajo language a weird succession of guttural, nasal, tongue-twisting sounds … we couldn’t even transcribe it, much less crack it.
Syllabic scripts occupy the middle ground, with between 50 and 100 syllabic characters. Beyond these two facts, Linear B was an unfathomable mystery.
Não existe utilidade prática em saber que π é irracional, mas, se podemos saber, então certamente seria intolerável não saber.
Jack Good, a veteran of Bletchley, commented: Fortunately the authorities did not know that Turing was a homosexual. Otherwise we might have lost the war.
He was a rather quirky worker, and he didn’t really fit into the day-to-day business of GCHQ. But in terms of coming up with new ideas he was quite exceptional. You had to sort through some rubbish so...
Had the Arabs merely been familiar with the use of the mono-alphabetic substitution cipher, they would not warrant a significant mention in any history of cryptography. However, in addition to employi...
Figure 6 The science of secret writing and its main branches.
Enigma was considered invulnerable, until the Poles revealed its weaknesses.
Enigma decipherments gave the locations of numerous U-boats, but it would have been unwise to attack every single one of them, because a sudden, unexplained increase in successful British attacks woul...
Each member of the school was forced to swear an oath never to reveal to the outside world any of their mathematical discoveries.
The numerous losses were either the result of natural misfortune or caused by a British spy who had infiltrated the German navy. The breaking of Enigma was considered impossible and inconceivable.
The Arab scholars were also capable of destroying ciphers. They in fact invented cryptanalysis, the science of unscrambling a message without knowledge of the key.
Diagonally polarized photons are in a quantum quandary when confronted by a vertical Polaroid filter.
The security of a cryptosystem must not depend on keeping secret the crypto-algorithm. The security depends only on keeping secret the key.
The letters a and l are the most common in Arabic, partly because of the definite article al-, whereas the letter j appears only a tenth as frequently.
Ron Rivest, one of the inventors of RSA, thinks that restricting cryptography would be foolhardy: It is poor policy to clamp down indiscriminately on a technology just because some criminals might be...
Rejewski had no idea of the day key, and he had no idea which message keys were being chosen, but he did know that they resulted in this table of relationships. Had