Key whitening

In cryptography, key whitening is a technique used to increase the security of block ciphers. It consists of steps that combine the data with portions of the key (most commonly using a simple XOR) before the first round and after the last round of encryption. DES-X was the first block cipher that used key whitening.

Key Whitening Media

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  Key whitening using the xor-encrypt-xor technique: a (short) Key is made longer with Key1 and Key2 parts