"Mitsubishi Electric Co., Ltd. and Nippon Telegraph and Telephone Corp. (NTT) developed a common key encryption algorithm called Camellia."Camellia converts a 128-bit data block into a cipher and vice versa. It was developed by upgrading the existing 64-bit symmetric-key encryption algorithms, including Mitsubishi's MISTY and NTT's FEAL.
"Although 64-bit encryption technology is in common use at present, both companies have decided to employ the 128-bit technology to achieve a higher level of security. It is aimed for uses such as IC cards, the Internet and wireless communications.
"Camellia is characterized by its suitability for both software and hardware implementation. It only uses substitution tables and logical operations (AND, OR and exclusive-OR), excluding arithmetic operations -- addition (ADD) and multiplication (MUL) -- from its encryption algorithm. That has made it possible to shrink cipher and decipher circuits. For example, its cipher circuits have only about 10K gates of transistors.
"What is more, even 8-bit microprocessors, which are commonly used in IC cards, can process the encryption quickly enough, because Camellia's processing units have been unified into 8 bits.
"Camellia supports 128-bit block size and 128-, 192-, and 256-bit key length, which is the same interface as Advanced Encryption Standard (AES), a standard being formulated by the federal government of the United States.
"Currently there are five candidate technologies to be adopted as the AES. Each of which, however, has merits and demerits. For example, one of them uses an algorithm being optimized by Pentium processors' instruction sets. Another slows down its process speed when it is executed by an 8-bit microprocessor.
"Mitsubishi and NTT plan to propose Camellia to the JTC1/SC27 of ISO/IEC, an international organization formulating standards for information security technologies, to make Camellia the industry standard.