We provide a
system that uses
blockchain technology to offer a will
data management service that is cost-effective, highly secure, and convenient to process, while being resistant to cyberattacks such as
quantum computer
cryptography and
ransomware. [Solution] The
system 100 includes means 13 for obtaining consent information of persons with access rights to will data regarding the
backup and restoration of will data, will
data management information 14, will
data management information setting acceptance means 15, will data management information setting / registration means 16,
smart contract for will data management 17,
death certificate confirmation monitoring means 18 for monitoring whether the
death certificate of the person concerned has been confirmed, and a
processing method based on the consent information of persons with access rights to will data using polynomial
secret sharing encryption processing and multiple authentications to render predetermined information meaningless, manage it in a distributed manner as files sorted into multiple points, and manage the file index information by encrypting it.