I'm currently studying for a cryptography exam. I've been given ciphertext that has been encrypted by a columnar transposition cipher. I've been given no shift key length or key word, the only thing I ...
Would the following affect the maximum message size limititaion of Blowfish and DES due their small 64 bit block size? Let's take Blowfish for example. You take a 256 bit Blowfish key, quickly ...
Could anyone explain how secure is bit level permutation? What is the most serious threat against the security of this kind of cipher? Thank you