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:
Dec. 21, 1999
Filed:
May. 16, 1997
Joseph M Kulinets, Stamford, CT (US);
Software Security, Inc., , CT (US);
Abstract
A self contained data medium is provided with an apparatus for generating a decrypting key for decrypting stored data. Frames of encrypted data are stored on the data medium such as a video or audio disk. Each frame of data includes a header which has a frame identification number. A reader reads each frame of data including the header with the frame identification number. The reader transmits the frame number to a transponder attached to the data medium. The transponder includes a decryption engine which calculates a decryption key from the frame number and a secret deciphering key stored in the transponder. The transponder transmits the decryption key to the reader which uses the decryption key to decrypt the frame of data. The system discourages both home copying and commercial piracy of the underlying program material.