| 摘要 |
PROBLEM TO BE SOLVED: To prevent the reception of a decipher key from becoming impossible in a receiver and a charging processing from becoming impossible in a key management device. SOLUTION: A cipher key communication method is for deciphering contents ciphered by a prescribed cipher system in the receiver, by using key information received from the key management device. At this time the key information for indicating a cipher key is generated in the key management device, corresponding to a key information request instruction for requesting the key information for deciphering the contents from the receiver and access from the receiver is inhibited. After performing the charging processing corresponding to the receiver, the access from the receiver to the key management device is permitted, the key information is transmitted from the key management device to the receiver which corresponds to the key information request instruction from the receiver, and the ciphered contents are deciphered in the receiver by using the key information. |
