| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve an encryption technique for a data processing apparatus so as to decrease the possibility of communication being decrypted by a third person.SOLUTION: A data processing apparatus encrypts processing object data as encrypted data, and records the encrypted data in a predetermined recording medium. The apparatus also decrypts and returns the encrypted data recorded in the recording medium to the processing object data. Encryption is performed in units of plaintext segment data that is created by segmenting the processing object data by a prescribed number of bits. The numbers of bits of the plaintext segment data is varied, and dummy data having a size of a number of bits matching the largest number of bits is mixed into the plaintext segment data other than plaintext segment data having the largest number of bits among the plaintext segment data.</p> |
