Abstract: The method of verifying an opinion includes, by an account module, receiving a request for identification information of the opinion (Ballot Stamp) from the user terminal; requesting a first random value to the user terminal; receiving a first homomorphic ciphertext from the user terminal; generating a second random value; storing a first value; generating a second homomorphic ciphertext from the Ballot Stamp; receiving a third homomorphic ciphertext obtained from a tag from an opinion verifying program module; and transmitting the second homomorphic ciphertext and the third homomorphic ciphertext to the user terminal. The method further includes, by the opinion verifying program module, receiving the tag obtained by decrypting the third homomorphic ciphertext, Ballot Stamp, and the opinion message, from the user terminal; and determining the opinion as being verified if the value calculated by the first arithmetic operation to the random value and Ballot Stamp is identical to the tag.

Abstract: The present disclosure relates to a method for registering an anonymous digital identity of a user with an identification information storage module in an environment including a user terminal, an account module, and the identification information storage module. The user terminal and the account module generate a first identification ID, a first token, a second random value, a second encryption value, a second value, and a first validation value through mutual communication. On the basis of the information, the identification information storage module generates a third hash value, a second token, an eighth value, and a second validation value through mutual communication with the user terminal. The account module validates the first token, the second hash value, and the first and second validation values, and registers the anonymous identity with the identification information storage module.

Abstract: The present disclosure relates to a method of establishing a digital identity that reserve a privacy of an entity. The method comprises a first step of receiving a validity verification value and verifying the value; a second step of a homomorphic encryption value of a tag based on a homomorphic encryption value of a identity verification ID; and a third step of associating an anonymous digital identity with identity verification information and storing them if a value which is calculated by carrying out a predetermined arithmetic operation to the homomorphic encryption value is identical to the tag.

Abstract: The method of verifying an opinion includes, by an account module, receiving a request for identification information of the opinion (Ballot Stamp) from the user terminal; requesting a first random value to the user terminal; receiving a first homomorphic ciphertext from the user terminal; generating a second random value; storing a first value; generating a second homomorphic ciphertext from the Ballot Stamp; receiving a third homomorphic ciphertext obtained from a tag from an opinion verifying program module; and transmitting the second homomorphic ciphertext and the third homomorphic ciphertext to the user terminal. The method further includes, by the opinion verifying program module, receiving the tag obtained by decrypting the third homomorphic ciphertext, Ballot Stamp, and the opinion message, from the user terminal; and determining the opinion as being verified if the value calculated by the first arithmetic operation to the random value and Ballot Stamp is identical to the tag.