Patent ID: 11956625
Assignee: BITKEY INC.
Field: Digital communication (Electrical engineering)
Classification: CPC H  E  G | IPC H

Claim 4:
5. A utilization control method for controlling use of a usage target object by using: a utilization control device that controls use of the usage target object by locking/unlocking, access control or encrypting/decrypting based on a use permit; and a use permit notification device that notifies the use permit to the utilization control device, wherein,
the use permit notification device:
stores the use permit that includes transaction information specifying usage conditions for using the usage target object, together with a signature on the use permit generated by using a predetermined private key, for each user identification information; and
on obtaining to user identification information, sends the use permit and the signature stored in connection with the user identification information to the utilization control device,
the utilization control device:
can communicate only via the Near Field Communication;
stores a hole data that includes a public key paired with the predetermined private key and is necessary for verification of the use permit; and
verifies the signature received together with the use permit from the use permit notification device by using the public key included in the hole data to refer to the transaction information included in the use permit when the verification being established, and lifts restriction on use of the usage target object if the conditions specified by the transaction information are satisfied.