| 摘要 |
PROBLEM TO BE SOLVED: To provide the music data distribution service system in which it is not required to carry a plurality of media, new music data are recorded/ reproduced and the possibility of violating the copyright is precluded. SOLUTION: This system is composed of a portable headphone device 1 and a music data distribution installation 2 that distributes music data to the portable headphone device 1, and the portable headphone device 1 sends the request of music data to the music data distribution installation 2, receives encrypted music data and a cryptographic key in response to the request from the music data distribution installation 2, uses the cryptographic key to decode the encrypted music data and uses a headphone 12 to reproduce the data. Then the music data distribution installation 2 sends the encrypted music data and its cryptographic key to the portable headphone device 1 in response to the request of the music data received from the portable headphone device 1 to the portable headphone device 1. |
