Patent ID: 11882218
Assignee: NEC CORPORATION
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 9:
10. The matching system according to claim 8, comprising:
a registration request apparatus that transmits encrypted data of the individual elements of the first vector which is a registration target and n-dimensional first vector to a storage apparatus; and
the storage apparatus is configured to:
calculate the third encrypted data of the n first transformed values by applying the first transformation to the first vector with the encrypted data of each element of the first vector being kept in an encrypted state, and
generate the fifth encrypted data by encrypting a sum of elements of the first vector and holds the third encrypted data of the n first transformed values and the fifth encrypted data obtained by encrypting a sum of elements of the first vector,
wherein, on reception of a matching request from the matching request apparatus, the matching apparatus obtains the third encrypted data of the n first transformed values from the storage apparatus, generates a random number, calculates the first encrypted data by operating the random number to individual items of the third encrypted data of the n first transformed values, and transmits the second encrypted data to the matching request apparatus,
wherein the matching request apparatus calculates the second transformed values by applying the second transformation to the second vector, performs an operation of each of the second transformed values and each of the first encrypted data received from the matching apparatus to calculate the second encrypted data by multiplying each of the second transformed values by each of values obtained by operating the random number to the first transformed values, and summing each value of the multiplication, and transmits the second encrypted data to the matching apparatus, and
wherein the matching apparatus calculates the fourth encrypted data of a sum of values of multiplication of the first transformed values by the second transformed values by removing the random number from the second encrypted data transmitted from the matching request apparatus, and adds the fourth encrypted data and the fifth encrypted data registered in the storage apparatus to obtain the encrypted data indicating the distance between the first and second vectors and transmits the encrypted data indicating the distance between the first and second vectors to the verification apparatus.