What could be the keylength of the
DES encryption if we have an output of
DES has a 56-bit key in 8-bytes. The length of the output depends on the length of the input, mode and padding, not the key.
Note: The LSb (least significant bit) of each key byte is reserved for parity, depending on the DES implementation parity may or not be checked.
See: Data Encryption Standard.
DES is the block cipher with the
- fixed key length of
- the fixed block size of
It is co called cryptographic primitive (something as building block for constructing real ciphers).
To cipher some message it must be first divided / padded to the integer number of
So the key length must be
DES is now considered not be safe (mainly because of that short key length). Triple DES (
3DES) is now (relatively simple) substitution for it (with the 3 times longer, i. e.