nEncrypt fixed-size
blocks
nciphertext =
Encrypt(key,cleartext)
ncleartext =
Decrypt(key,ciphertext)
nEncrypt function
converts blocks of cleartext bits to ciphertext
bits
nDecrypt function
converts back
nIf the key is wrong,
you get the wrong result
nShouldn’t be
possible to derive key given cleartext, ciphertext
pairs
nExamples include
DES, 3DES, AES