| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a content receiver capable of restarting the transmission of contents without newly acquiring a key even when a content transmission is temporarily interrupted. <P>SOLUTION: The content receiver 1 for receiving contents is provided with: a key exchanging part 12 for exchanging a key that is valid only for a predetermined period when the key is used when the content is encrypted with a content transmitter for transmitting content; a receiving part 18 for receiving the content encrypted by using the key; a detecting part 13 for detecting that a period when the key is not used reaches the predetermined period; and a transmitting part 15 for transmitting information for preventing the key from being invalid to the content transmitter when it is detected that the period when the key is not used reaches the predetermined period. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
