DECIPHERING DEVICE, DEVICE AND METHOD FOR CRYPTOGRAPHIC COMMUNICATION, AND STORAGE MEDIUM THEREFOR

摘要

PROBLEM TO BE SOLVED: To improve the security of a polynomial cryptogram. SOLUTION: A plaintext message is processed by non-linear coding, and enciphered into a ciphertext degenerated by a polynomial cryptogram. At the time of decoding, the message corresponding to the non-linear code in the original image of the ciphertext is decoded as the plaintext message.