RECORDING SYSTEM, PLAYBACK SYSTEM, KEY DISTRIBUTION SERVER, RECORDING DEVICE, RECORDING MEDIUM DEVICE, PLAYBACK DEVICE, RECORDING METHOD, AND PLAYBACK METHOD

摘要

To protect rights of a copyright owner of digital content, technology is required to prevent digital content on a recording medium from being copied onto another recording medium and played back. A key distribution server securely receives a media unique key from a recording medium device, generates a first title key different for each content, encrypts the generated first title key with the media unique key, encrypts the content with the first title key, and transmits the encrypted first title key to the recording medium device and the encrypted content to the recording device. The recording device securely receives the encrypted content from the key distribution server and the first title key and a second title key from the recording medium device, decrypts the encrypted content with the first title key, encrypts the decrypted content with the second title key, and transmits the encrypted content to the recording medium device.