METHOD AND CIRCUIT FOR BLOCK CIPHERING, CIPHERING DEVICE, METHOD AND CIRCUIT FOR BLOCK DECIPHERING, AND DECIPHERING DEVICE

摘要

PROBLEM TO BE SOLVED: To simplify the constitution of a variable length block ciphering circuit and to reduce load of the circuit on a host computer.;SOLUTION: A plain memory 11 and a ciphering circuit 13 to conduct a ciphering process or a deciphering process of original data in terms of a block unit are provided. Then, the original data are transferred to the memory 11 from the outside. The transferred data are supplied to the ciphering circuit 13 which conducts a ciphering process or a deciphering process in the block unit. Then, the original data of the memory 11 are replaced by the data which are the results of the above process. When all of the original data transferred to the memory 11 are replaced by the data of the results of the above process, the the data of the results of the above process are outputted to the outside.;COPYRIGHT: (C)2004,JPO