| 摘要 |
An authentication method and an authentication apparatus are provided to prevent a large number of devices from being registered by adjusting the number of registerable devices in an authentication list. A random number generator(470) generates a first random number. A transmitter(460) transmits a first random number, a public key of a first device, and expiry information of the first device. A receiver(410) receives a second random number and expiry information of a second device. The second random number is generated by the second device and encrypted by the public key of the first device, when the first device is not expired. A decoder(420) decodes the second random number using a secret key of the first device. A device expiry determining unit(430) determines whether the second device is expired according to the expiry information of the second device. A key generator(440) selectively generates a temporary key by using the first and second random numbers and a determined result from the device expiry determining unit. An encrypting unit(450) encrypts the public key for encrypting a contents key using the temporary key, when the temporary key is generated. |
