Data encrypting/decrypting conversion methods and apparatuses and data communication system adopting the same

• Main Authors: Aikawa, Makoto, Takaragi, Kazuo, Koreeda, Hiroyuki, Sasamoto, Manabu, Okamoto, Hiroo, Noguchi, Takaharu, Furuya, Soichi, Hirahata, Shigeru
• Format: Patent
• Language: English
• Published: 12.08.2003

The present invention relates to encryption/decryption techniques for encrypting/decrypting digital data transferred among computers, home-use-destined electric/electronic equipment and the like. Encrypting/decrypting conversion method and apparatus capable of controlling dynamically cyclic shift independent of data to undergo encrypting/decrypting conversion includes two or more different fixed circulating shift processing means for shifting cyclically the data by a fixed bit number leftward or rightward, a cyclic shift processing selecting means for selecting fixed cyclic shift processing means. The selecting sequence determined by the cyclic shift processing means is determined on the basis of data for determining the shift number selecting sequence.