Samsung Sds Co., Ltd.

Snu Rdb Foundation

Korea Advanced Institute of Science and Technology

Seoul National University

Kookmin University

Hyo Jin Yoon

Jung Hoon Sohn

Eun Kyung Kim

Duk Jae Moon

Jung Hee Cheon

Seon Young Lee

Joo Hee Lee

Ji Hoon Cho

Jin Hyuck Jeong

Young Hyun Kim

Seung Hyun Kang

Jin Young Kim

Joo Young Lee

Ki Hyo Moon

Seong Kwang Kim

Jinhyuck Jeong

Jin Yeop Chang

Eunkyung Kim

Ji Hoon Kwon

Tae Ho Lee

Min Jung Kim

Won-Il Lee

Kyu Young Choi

Chang Hoon Lee

Hyung Lee

Won Il Lee

Seung Ro Joo

Jin Cheol Ha

Soon Mok Kwon

Dong Guk Han

Won Seok Choi

Sang Yub Lee

Jang Hyuk Ahn

Kyoo Hyung Han

Chung Hyeok Lee

Bo Yeon Sim

Jae Won Huh

Tae Kyoung Kwon

Young Seon Lee

Kyung Seung Lee

Soo Yeon Shin

Jae Seung Han

Il Ju Kim

Jong Hyeok Lee

Ki Sang Kwon

Keon Hee Choi

A method for training an analysis model according to an embodiment includes receiving synthetic data for original data from a client apparatus, determining a hyperparameter value for analysis model training using the synthetic data, receiving a ciphertext for the original data from the client apparatus, and training the analysis model using the determined hyperparameter value and the received cipher text.

Method and apparatus with ciphertext training analysis model

A method for generating a key stream according to an embodiment includes generating r round keys that are each N-dimensional integer vectors including elements of an integer setdefined based on a prime number t, based on a random bit string, an encryption counter, and a secret key that is an N-dimensional integer vector consisting of elements of the integer set, generating a first round output vector xby performing a modular addition operation on an initial vector and a first round key RKof the r round keys with the prime number t as a modulus, and generating a key stream that is an N-dimensional integer vector consisting of elements of the integer setfrom the first round output vector xby using a second to r-th round keys of the r round keys, and one or more first round functions and a second round function.

Method and apparatus for generating key stream

In a method of generating a secret key according to an embodiment, a share of each of a user and a plurality of other users for a secret key of the user are generated, the share of each of the plurality of other users is provided to a user terminal of each of the plurality of other users, a share of the user for a secret key of each of the plurality of other users is received from the user terminal of each of the plurality of other users, and a new secret key of the user is generated using the share of the user for the secret key of the user and the shares of the user for the secret key of each of the plurality of other users.

Apparatus and method for generating secret key, apparatus and method for generating evaluation key

A method for preventing side-channel attack according to an embodiment includes generating an order table which includes a position index value for each bit value of a bit string that is secret information to be generated through a decryption algorithm of an NDegree Truncated Polynomial Ring Units (NTRU) LPRime algorithm, shuffling a sort order of the position index value for the each bit value in the order table based on a random number, determining a generation order for the each bit value according to the sort order of the position index value for the each bit value in the order table, and generating the secret information through the decryption algorithm. The secret information is generated by generating the each bit value according to the determined generation order.

Apparatus and method for preventing side channel attack for NTRU LPRime algorithm

A method of generating a secret key according to one embodiment includes generating a share of each of a user and a plurality of other users for a secret key of the user, providing the share of each of the plurality of other users to a user terminal of each of the plurality of other users, receiving a share of the user for a secret key of each of the plurality of other users from the user terminal of each of the plurality of other users, and generating a new secret key of the user using the share of the user for the secret key of the user and the shares of the user for the secret key of each of the plurality of other users.

A method for encryption according to an embodiment includes generating a ciphertext for a secret key that is an integer vector by using an integer-based first homomorphic encryption algorithm, generating a key stream that is the integer vector from a nonce and the secret key by using a key stream generator, encoding the key stream by using a message encoding function of the first homomorphic encryption algorithm, encoding a message that is a real vector by using a message encoding function of a real number-based second homomorphic encryption algorithm, generating a ciphertext for the message by using a result of the encoding of the key stream and a result of the encoding of the message, and transmitting the nonce, the ciphertext for the secret key, and the ciphertext for the message to an apparatus for converting a ciphertext.

Apparatus and method for encryption, apparatus and method for converting ciphertext

A method for data analysis according to an embodiment includes acquiring, from a client device, a ciphertext for a precomputation result generated by applying some of a plurality of operations for performing an analysis algorithm based on target data to the target data, and generating an encrypted computation result for remaining operations of the plurality of operations by using the ciphertext.

Apparatus and method for data analysis

A method for performing an operation according to an embodiment includes assigning an error value to encrypted data; and performing a homomorphic operation for an approximation function, which is obtained by approximating a target function, by using, as an input value, the encrypted data to which the error value is assigned.

Apparatus and method for performing operation using approximation function

An apparatus for set intersection operation according to an embodiment includes a ciphertext acquisition unit configured to acquire a ciphertext for a first vector corresponding to a first subset of a universal set including a plurality of elements from an encryption apparatus, a transform unit configured to generate a second vector corresponding to a second subset of the universal set, a computation unit configured to generate a ciphertext for a third vector corresponding to an intersection of the first subset and the second subset, based on the ciphertext for the first vector and the second vector, and a ciphertext providing unit configured to provides the ciphertext for the third vector to the encryption apparatus.

Apparatus and method for set intersection operation

A method for performing an operation according to one embodiment includes performing a homomorphic operation using one or more ciphertexts that are homomorphically encrypted based on an encryption key, determining a count value for a ciphertext generated through the homomorphic operation based on count values for each of the one or more ciphertexts, requesting a key management apparatus, which holds the encryption key and a decryption key corresponding to the encryption key, to re-encrypt the generated ciphertext based on the determined count value, acquiring, from the key management apparatus, a ciphertext generated by re-encrypting the generated ciphertext through decryption based on the decryption key and encryption based on the encryption key; and determining a count value for the acquired ciphertext to be a preset initial value.

Method and apparatus for performing operation using encrypted data

Provided are identifier (ID)-based encryption and decryption methods and apparatuses for the methods. The ID-based encryption method includes having, at a transmitting terminal, a transmitting-side private key corresponding to a transmitting-side ID issued by a key issuing server, generating, at the transmitting terminal, a session key using the transmitting-side ID, a receiving-side ID, and the transmitting-side private key, extracting, at the transmitting terminal, a secret key from at least a part of the session key, and encrypting, at the transmitting terminal, a message using a previously set encryption algorithm and the secret key.

Method and system for ID-based encryption and decryption

Wireless network connection control method of performing control for establishing and releasing wireless network connection with another device when impacts are applied to devices, application program control method of performing control for setting and executing application program when impacts are applied to devices, and device including wireless network connection control function and application program control function which use a device impact are disclosed. According to the present invention, provided is a wireless network connection control method of a device using a device impact, including generating a corresponding impact event when physical impact applied from the outside is sensed, transceiving a search message between devices based on a time at which the impact event occurred, searching for another device in which the impact event has occurred at the same time, and performing a predetermined protocol with a corresponding device according to a search result and establishing an inter-device wireless network connection.

Wireless network connection controlling method using device impact, application program controlling method, and devices thereof

Provided are an identity (ID)-based encryption and signature method and a terminal that use an ID of a transmitter or a receiver as a part of the filename or the extension of a file transmitted to the receiver by the transmitter. Accordingly, it is possible to enable a user to visually recognize that the file has been provided with security. Also, it is possible to designate an associated program for the extension, and the user can easily decrypt or verify the file through the designated associated program.

ID-based encryption and signature method and terminal

A private key generation apparatus for generating a private key corresponding to a user ID using the user ID as a public key is disclosed. When a user ID is input, an ID conversion unit outputs a specific element value of a discrete logarithm cyclic group having a one-to-one correspondence relationship with an input user ID. A private key calculation unit calculates a discrete logarithm result value based on the output specific element value of the discrete logarithm cyclic group and calculates a private key having a one-to-one correspondence relationship with the user ID. According to the present invention, it is possible to concretely propose a method of calculating a secret key, capable of guaranteeing a one-to-one correspondence relationship between the ID and the private key by applying a method of calculating a discrete logarithm using the pre-computation table in an ID-based encryption system.

Apparatus and method for generating secret key for ID-based encryption system and recording medium having program recorded thereon for causing computer to execute the method

Disclosed are a data transmission/reception apparatus and method. A secret key generation unit uses a user ID as a public key to generate a secret key corresponding to the user ID. An encryption/decryption unit sets a user ID intended to receive data as an input value to encrypt the data using a certain method and decrypt the encrypted data using a certain method on the basis of a secret key corresponding to a user ID of a receiver generated by the secret key generation unit. The transmission apparatus and method according to the present invention allow for secure communication between terminals without server intervention by encrypting data using an ID-based encryption technique for safe data communication and then communicating the encrypted data.

Apparatus and method for transmitting data, and recording medium storing program for executing method of the same in computer

Growing community of inventors

Seoul, South Korea

Hyo Jin Yoon