Abstract:
The present invention relates to a method and device for verifying data ownership. The user may verify whether the server actually owns the data to be uploaded by him, and the server may simultaneously verify whether the user actually owns the data.
Abstract:
Disclosed herein is an apparatus and method for verifying data validity. The method performed by the apparatus includes generating a zero knowledge proof key pair and a certificate using a key generation algorithm of zero knowledge proof in response to a request from a first device to issue a key, generating a verification certificate by verifying validity and quality of data after receiving the data and a verification request from the first device, and performing, by the first device, zero knowledge proof for the data in response to a proof request from a second device that buys the data possessed by the first device.
Abstract:
The present invention relates to a compressed encryption and decryption apparatus comprising: an interface receiving a public key, a secret key and a compression ratio; a memory storing instructions for encryption and decryption of plaintexts; and a processor encrypting and decrypting plaintexts according to the instruction, wherein the instruction comprises instructions performing; generating an extended public key and an extended secret key by revising the public key and the secret key according to the compression ratio; outputting the extended public key; receiving compressed ciphertext; and decrypting the compressed ciphertext using modulo operation for multiplication of the extended secret key and the compressed ciphertext.
Abstract:
Disclosed herein are an apparatus for generating the privacy-protecting document authentication information and a method of performing privacy-protecting document authentication. The apparatus for generating the privacy-protecting document authentication information includes an electronic signature information generation unit, a multi-dimensional code generation unit, and a multi-dimensional code output unit. The electronic signature information generation unit generates electronic signature information for the content of an input document. The multi-dimensional code generation unit generates a multi-dimensional code corresponding to the generated electronic signature information. The multi-dimensional code output unit outputs the generated multi-dimensional code onto the document.
Abstract:
A multi-user searchable encryption system includes a key generation center to issue a private secret key to a user and trace information regarding a user who has generated an index, and a user terminal device to generate an index for searching for a database using the private secret key. The multi-user searchable encryption system includes a database (DB) server that verifies the index generated by the user terminal device and searches for corresponding data to the verified index.
Abstract:
Disclosed herein is a method for encoding order information. The method may include generating multiple binary trees, preparing multiple different secret keys, determining a binary tree corresponding to any one secret key selected from among the multiple secret keys, and encoding the order information of the determined binary tree.
Abstract:
Disclosed herein are a key generation apparatus and method based on machine learning. The key generation method includes generating, by first and second key generation apparatuses, first and second commit values, and uploading the first commit value and the second commit value to an external repository, training, by the first and second key generation apparatuses, a neural network so as to match weight values with each other, sharing, by the first and second key generation apparatuses, the first and second commit values with each other, comparing shared first and second commit values with uploaded commit values, and then verifying the commit values, and when verification of the commit values has succeeded, generating, by the first and second key generation apparatuses, hash values using the matched weight value, verifying whether the hash values are identical to each other, and generating a session secret key based on a result of verification.
Abstract:
A method for secure distributed data management for dynamic data includes segmenting original data into multiple pieces, generating state information pertaining to row-based data configured with data blocks, and generating additional information for recovering the state information and the row-based data. The data blocks, corresponding to the segmented data, are stored in data servers, and each of the data servers stores data blocks selected at an interval corresponding to the number of data servers in order to store the segmented data.
Abstract:
A method for storing an encrypted file by a server is provided. The server receives a first encrypted file identifier from a client. The server generates a random number and transmits the random number to the client, when the first encrypted file identifier is present in a first database. The server generates a first verification value using the random number. In addition, the server confirms whether or not the client possesses a first encrypted file corresponding to the first encrypted file identifier among encrypted files stored in a second database by comparing the first verification value and a second verification value based on the random number with each other, when receiving the second verification value from the client.
Abstract:
Disclosed herein are an order-preserving encryption method and apparatus. The order-preserving encryption method may include when plaintext data is received from a client, storing a ciphertext database (DB), generated by encrypting the plaintext data, and a search index in a server, when a request for a range search query is received from the client, converting the range search query into a search index query statement, querying the server including search indices for the search index query statement, and querying the ciphertext DB of the server for an index ciphertext received in response to the query, and decrypting a ciphertext received as a response from the ciphertext DB and then transferring a plaintext-type response to the query statement to the client.