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Output Feedback Mode

Tags
cryptography

A mode of use for cipher-blocks which encrypts a sequence of input blocks (for example with ECB) to produce a sequence of intermediate output blocks which are XORed with the plaintext to produce ciphertext blocks.

Note: The first input-block is an initialisation-block IV.

Subsequent input-blocks are output-blocks from previous rounds.

This approach essentially converts a block-cipher into a stream-cipher.

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