Camellia
Camellia is a symmetric block cipher jointly designed by Mitsubishi and NTT, using 128-bit blocks with 128/192/256-bit keys, and was adopted as a recommended algorithm by NESSIE and CRYPTREC.
Purpose
It offers an alternative with security strength comparable to AES but a different structure, and is widely used in Japan and South Korea and in IETF protocols.
Mechanism
It is a Feistel network (18 rounds for 128-bit keys, 24 rounds for 192/256-bit keys) combining S-boxes (similar to AES) with P functions. The key schedule derives the subkeys for each round. Its structure differs from AES, providing design diversity.
Use cases
- TLS cipher suites (preferred in Japan and South Korea)
- IPsec ESP
- Japanese e-government
- Optional algorithm in IETF protocols
Examples
- Input
key=128bit, data=16bytesOutput16-byte ciphertextNESSIE recommended
Common errors
- Using Camellia on Western systems that lack hardware acceleration
- Evaluate platform support, or use AES-NI instead
Related terms
AES
The Advanced Encryption Standard (AES) is the symmetric block cipher NIST standardized in 2001, supporting 128/192/256-bit keys, and is the de facto standard of modern encryption. GLOSSARY
Serpent
Serpent is a symmetric block cipher designed by Ross Anderson et al. for the AES competition, using 128-bit blocks with 128/192/256-bit keys, known for its large security margin. GLOSSARY
Block Cipher
A block cipher is a symmetric cipher that encrypts and decrypts fixed-length blocks (e.g., 128 bits) and requires a mode of operation to handle arbitrary-length data. GLOSSARY