In Cryptography, a block cipher is a keyed permutation from N-bit blocks to N-bit blocks.
Modes of operation
Electronic Code Book (ECB)
- Use the key with the block cipher to get your N-bit to N-bit permutation.
- Go over the plaintext in blocks, encrypt each block using the raw block cipher.
- There is no IV. With the same key, the same N-bit block always encrypts to the same ciphertext.
Counter mode (CTR)
- Instead of putting the plaintext through the block cipher, counter mode instead encrypts an incrementing counter to generate a keystream.
- The plaintext is then XOR’ed with the keystream.
Citation
If you find this work useful, please cite it as:
@article{yaltirakli,
title = "Block cipher",
author = "Yaltirakli, Gokberk",
journal = "gkbrk.com",
year = "2024",
url = "https://www.gkbrk.com/block-cipher"
} Not using BibTeX? Click here for more citation styles.
IEEE Citation Gokberk Yaltirakli, "Block cipher", November, 2024. [Online]. Available: https://www.gkbrk.com/block-cipher. [Accessed Nov. 12, 2024].
APA Style Yaltirakli, G. (2024, November 12). Block cipher. https://www.gkbrk.com/block-cipher
Bluebook Style Gokberk Yaltirakli, Block cipher, GKBRK.COM (Nov. 12, 2024), https://www.gkbrk.com/block-cipher