Data Encryption Standard (DES)
Contains all constants for the DES Block
**************************************************************************** Interface use by a symmetric block
Triple DES (3DES)
Triple DES (3DES)
Encrpytion : Decrytpion :
plaintext plaintext (64 bits) | | ----------------- ---------------- | DES encrypt |<-- K1 -->| DES decrypt | ----------------- ---------------- | | ----------------- ---------------- | DES decrypt |<-- K2 -->| DES encrypt | ----------------- ---------------- | | ----------------- ---------------- | DES encrypt |<-- K3 -->| DES decrypt | ----------------- ---------------- | | ciphertext ciphertext (64 bits)
key = Concatenation(k1 , k2 , k3) = 3*64 bits = 192 bits
Define some usefull funtion
Data Encryption Standard (DES)
_ | | -- Plaintext --->| DES |-- Ciphertext --> (64 bits) |_| (64 bits) | Key (56 bits) | Key + parity (64 bits)