The input to the encryption processes of the CBC, CFB, and OFB modes includes, in addition to the plaintext, a data block called the initialization vector (IV), denoted IV. The IV is used in an initial step in the encryption of a message and in the corresponding decryption of the message.

What is the difference between CBC and CFB?

Cipher Feedback (CFB) mode is very similar to CBC; the primary difference is that CFB is a stream mode. It uses feedback (the name for chaining when used in stream modes) to destroy patterns. Like CBC, CFB uses an initialization vector that destroys patterns and errors propagate.

How does CFB encryption work?

Ciphertext feedback (CFB) is a mode of operation for a block cipher. ... CFB uses a block cipher as a component of a random number generator. In CFB mode, the previous ciphertext block is encrypted and the output is XORed (see XOR) with the current plaintext block to create the current ciphertext block.