发明名称 |
SYSTEM FOR PROVIDING TIME DEPENDENT CONDITIONAL ACCESS |
摘要 |
A source transmits ( 10 ) successive keys encrypted in encryption control messages and information in an encrypted form at is successively decryptable with the successive keys. A decoder ( 122 ) decrypts the information. A secure device ( 14 ) receives the encryption control messages, decrypts the keys from the messages and supplies the keys to the decoder ( 122 ). The secure device ( 14 ) maintains a time value. The secure device ( 14 ) controls the supply of the keys dependent on the time value, and increments the time value in response to reception of respective ones of the encryption control messages. |
申请公布号 |
AU2002367373(A1) |
申请公布日期 |
2003.07.24 |
申请号 |
AU20020367373 |
申请日期 |
2002.12.09 |
申请人 |
KONINKLIJKE PHILIPS ELECTRONICS N.V. |
发明人 |
JILLES VENEMA;FRANCISCUS, L., A., J. KAMPERMAN |
分类号 |
G06F21/24;G06F21/00;H04L9/08;H04N1/00;H04N5/00;H04N7/16;(IPC1-7):H04N1/00 |
主分类号 |
G06F21/24 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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