Data Certification Device, Non-transitory Computer-readable Medium, and Method Therefor

Abstract

A file is created in which digital data and a certificate are integrated and content authentication for the digital data and the certificate are performed simultaneously. A data authentication device ( 1 ) is provided with: an original data receiving means which is communicably connected to a user terminal ( 2 ) and a timestamp provision device ( 3 ), and receives original data to be authenticated from the user terminal ( 2 ); an intermediate file creation means which creates an authentication file corresponding to the original data, and attaches the actual original data to the authentication file to create an intermediate file; a timestamp request means which transmits the intermediate file to the timestamp provision device ( 3 ); a date/time security information acquisition means which receives from the timestamp provision device ( 3 ) date/time security information containing date/time information and a hash value for the intermediate file; an authenticated file creation means which embeds the received date/time security information in the intermediate file and creates an authenticated file; and an authenticated file transmission means which transmits the authenticated file to the user terminal ( 2 )

1 - 8 . (canceled) 
     
     
         9 . A method for certifying existence of digital data at a time point, using a system of network connected devices that includes
 a user terminal at a first location,   a data certification device at a second location, and   a time-stamping device at a third location,   wherein the first, second, and third locations are different from one another;   
       the method comprising:
 receiving, at the data certification device from the user terminal, original digital data to be certified; 
 creating, at the data certification device, a certificate file containing date and time of receipt of the received original digital data, 
 attaching, at the data certification device, the original digital data to the certificate file to create an intermediate file in which the original digital data is unaltered; 
 feeding, at the data certification device, the intermediate file into a predetermined hash function to calculate a hash value; 
 transmitting, from the data certification device to the time-stamping device, only the calculated hash value; 
 receiving, at the data certification device from the time-stamping device, date and time certification information indicative of when the time-stamping device received the hash value; 
 embedding, at the data certification device, the date and time certification information into the intermediate file to create a certified file.