25 мая 2016 г. · I would like to know how to find the keyword of the Playfair cipher, given some ciphertext and the corresponding plaintext.

9 окт. 2016 г. · The quick and dirty way would be to write a computer program to try all the remaining possible key letters in the ? positions and print out the resulting ...

15 февр. 2021 г. · You could probably even solve this with pen and paper by attempting a partial decryption with the parts of the key you already have, then ...

21 янв. 2015 г. · Basically it starts with a random key (assuming it's the best one) and decrypts the cipher. The resulting clear text is scored using a fitness function.

21 мар. 2021 г. · The best place to start is by looking for common digraphs (pairs of letters). There are lists of the most common digraphs in English and if you have a long ...

18 сент. 2018 г. · The Playfair cipher as you've described it cannot encrypt all messages; specifically, it cannot handle messages where two consecutive identical letters fall ...

21 сент. 2011 г. · The first thing you want to do is convert the text into numbers as many classic ciphers are mathematically-based (or at least easy represented mathematically).

18 сент. 2012 г. · If it is a simple substitution cipher, there are a few standard techniques: Frequency analysis. Count how many times each letter appears in the ciphertext.

15 окт. 2015 г. · I've got a ciphertext without knowing about the algorithm or key used encrypting the plaintext. I assume that this cipher is not too hard (no AES eg) to crack.

13 мар. 2020 г. · If I do not have access to the key square and the keyword, and I am just given the ciphertext and a string of numbers, how do you decipher it?