A block cipher is an encryption algorithm which encrypts fixed-size blocks of plaintext to same-sized blocks of ciphertext. For good ciphers every bit of the ciphertext block depends on every bit of the plaintext block and every bit of the key.
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Hash function from narrower block cipher operated in CBC-encryption mode?
I am trying to build a public hash function (thus collision-resistant and preimage-resistant, and more generally behaving like a random oracle), with input a message $M$ of fixed size $|M|=m\cdot b$ ...
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Are Stream Ciphers Less Secure?
This is by no means a scientific observation, but it seems to me that stream ciphers receive a lot less attention than block ciphers. Is there any reason for this? (Is it because block ciphers are ...
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Byte location of plaintext vs ciphertext when using a block cipher or stream cipher
I know that when you use a stream cipher you are just XOR'ing the plain text with the PRNG stream, such that you know if a specific byte is in position 3 of the plain text it will still be in ...
