| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To solve the problem that, when a viewing validity of contents expires while the contents are reproduced and when a recording medium is removed, a decryption key may be residual on the recording medium even after the expiration of the viewing validity. <P>SOLUTION: A content reproducing device includes: a viewing validity determining section 301 for determining whether a viewing validity expires; a decryption key temporary storage section 106 for temporarily storing a decryption key 104; a decryption key moving section 111 for moving the decryption key from a recording medium 102 to the decryption key temporary storage section and returning the decryption key onto the recording medium; a content protection control section 302 for controlling move and return of the decryption key; and a content reproducing section 305 for reproducing contents 103 using the decryption key. Upon receipt of a reproduction starting instruction, the content protection control section performs control to move the decryption key from the recording medium to the decryption key temporary storage section by means of the decryption key moving section, to return the decryption key onto the recording medium if the viewing validity does not expire when reproduction of contents is finished, and not to return the decryption key onto the recording medium if the viewing validity expires. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
