| 摘要 |
PROBLEM TO BE SOLVED: To cipher data and a redundant byte attached to it while keeping the error correcting ability of original data by preparing a redundant column through the use of an error correcting code generating system to be applied to data to cipher. SOLUTION: A storing device drive 103 reads original data including an error correcting code from a medium and through the use of a pseudo random number generator 713 preparing the redundant column for correcting error, prepares data block including a random number of the same size as the original data. The error correcting code is added to this data block by using the error correcting code generating system equal to the original data. An exclusive OR of the original data and a random data block is taken to form a ciphered data block. Obtained data block is sent to a host processor on a data bus 704. The host 701 executes error correction to this data block and sends error corrected data to an MEPG decoder 702 with the same random number generator 712 as a storing device 703.
|
