| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent content of a browsing object from being reproduced without reproducing subcontent such as a commercial. <P>SOLUTION: This content distribution and browsing system is configured so as to distribute subcontent SC<SB>1</SB>, a subcontent encryption key Ksc<SB>1</SB>, encrypted subcontent E(Ksc<SB>1</SB>, K<SB>1</SB>¾¾Ksc<SB>2</SB>¾¾SC<SB>2</SB>), to, E(Ksc<SB>L-2</SB>, K<SB>L-2</SB>¾¾Ksc<SB>L-1</SB>¾¾SC<SB>L-1</SB>), and E(Ksc<SB>L-1</SB>, K<SB>L-1</SB>¾¾SC<SB>L</SB>), and encrypted content E(K<SB>M</SB>, C) to thereby be able to prevent distributed keys K<SB>1</SB>to K<SB>L-1</SB>of a content encryption key K<SB>M</SB>required to decrypt encrypted data from being acquired unless subcontent SC<SB>2</SB>to SC<SB>L</SB>are sequentially reproduced while sequentially decrypting the encrypted subcontent after reproducing the subcontent SC<SB>1</SB>. Then, the content of a browsing object can be prevented from being reproduced. <P>COPYRIGHT: (C)2009,JPO&INPIT |
