License Info management system, user terminal, right clamper terminal, the method and License Info management program of License Management.

摘要

PROBLEM TO BE SOLVED: To apply a block chain, which is used for a transaction of digital virtual currency, to content permission management.SOLUTION: A user terminal 1 comprises: a key generation unit 11 for generating a first key pair and a second key pair; a permission request unit 13 for performing, by using a secret cipher key for the first key pair, an electronic signature on a permission request including a public cipher key for the second key pair to transmit the signed permission request; and a content utilization unit 14 for acquiring, by using a secret decryption key for the second key pair, a content decryption key from permission information transmitted by a right holder terminal 2 to utilize a content. The right holder terminal 2 comprises: a key management unit 21 for storing a third key pair and the content decryption key; a permission verification unit 23 for verifying the received permission request; and a permission issue unit 22 that encrypts the content decryption key by using the public cipher key for the second key pair included in the permission request, and performs, by using a secret cipher key for the third key pair, an electronic signature on permission information including the encrypted content decryption key to transmit the signed permission information. The permission request and permission information are transmitted/received through a block chain.SELECTED DRAWING: Figure 1