Camellia is a 128-bit block cipher, which was developed by
NTT and Mitsubishi Electric Corporation. Camellia supports 128-bit
block size and 128-, 192-, and 256-bit keys, i.e. the same interface
specifications as the Advanced Encryption Standard (AES). Efficiency
on both software and hardware platforms is a remarkable characteristic
of Camellia in addition to its high level of security. It is confirmed
that Camellia provides strong security against differential and linear
cryptanalysis. Compared to the AES finalists, i.e. MARS, RC6,
Rijndael, Serpent, and Twofish, Camellia offers at least comparable
encryption speed in software and hardware. An optimized
implementation of Camellia in assembly language can encrypt on a
Pentium III (800MHz) at the rate of more than 276 Mbits per second,
which is much faster than the speed of an optimized DES
implementation. In addition, a distinguishing feature is its small
hardware design. The hardware design, which includes both encryption
and decryption, occupies approximately 11K gates, which is the
smallest among all existing 128-bit block ciphers as far as we know.