抄録
Encryption is used as a means of ensuring the confidentiality of information communications over the Internet, and many of these methods use a hybrid method of secret key cryptography and public key cryptography. Secret key cryptography is suitable for encrypting and transferring large amounts of data, but the key must be distributed in advance. In our information and communications network society, where we communicate with an unspecified number of people, the problem of key distribution is solved by public key cryptography. The security of public key
cryptography currently in practical use relies on the difficulty of efficiently solving the prime factorization problem of large numbers and the discrete logarithm problem on elliptic curves. However, with the advent of practical quantum computers, it has been shown that these problems may be solved efficiently. Of course, secure data transfer methods for quantum communication have also been proposed, but it is also important to develop encryption methods using current communication means that cannot be decrypted within a practical time frame even by quantum computers.
This type of encryption scheme is collectively called PQCC, and several schemes have been proposed. Here, we propose a scheme that uses a self-dual code over the integer quotient ring.
