Cryptography: Avalanche Effect in DES

•A desirable property of any encryption algorithm is that a small change in either the plaintext or the key should produce a significant change in the ciphertext.

•In particular, a change in one bit of the plaintext or one bit of the key should produce a change in many bits of the ciphertext.

•This is referred to as the avalanche effect. If the change were small, this might provide a way to reduce the size of the plaintext or key space to be searched.