The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 27, 1999
Filed:
Dec. 31, 1996
Michael Tomoyuki Hayashi, Aurora, CO (US);
Michael Brian Adams, Castle Rock, CO (US);
Louis Dew Williamson, Denver, CO (US);
Time Warner Cable, a division of Time Warner Entertainment Company, L.P., Stamford, CT (US);
Abstract
An apparatus/method for descrambling a TV cable system transmission that been scrambled using an unknown scrambling algorithm. Insertion apparatus inserts a known visual/electrical characteristic into the TV transmission prior to scrambling by the unknown scrambling algorithm. The scrambled TV transmission, the scrambled insert-characteristic, and an encrypted message that defines the unscrambled insert-characteristic, are sent to all set-tops within the cable system. A set-top descrambler at each system-authorized set-top operates to descramble the scrambled insert-characteristic. The encrypted message is decrypted at each system-authorized set-top, to thereby reproduce the unscrambled insert-characteristic. Comparing apparatus compares the reproduced unscrambled insert-characteristic with the descrambled insert-characteristic, and thereby generates a control signal that is used to control the set-top descrambler to descramble the scrambled TV transmission in a manner that is compatible with the unknown scrambling algorithm.