| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a content transmission system and method that can recognize information indicating whether the number of receiving devices should be limited, even if the receiving devices do not have a decryption function, and that can fully protect content. <P>SOLUTION: The content transmission system includes an encrypting part 16 for encrypting an inputted content based on a predetermined encryption mode; a header creating part 17 for creating a header part including the encryption mode used in an encryption process; and sending means 18, 19 for sending a packet resulting from the combining of the header part created and the content encrypted. The header creating part 17 adds to the header part control information showing whether the number of receiving devices 12 is limited, along with the encryption mode. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
