Smart-card based access control system with improved security
CA 2196407 C · Owner: Thomson Consumer Electronics, Inc. · Inventors: Chaney, John William
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A smart card that includes a descrambler for descrambling entitlement information and data provides improved access control by controlling the manner in which the entitlement information portion of the data stream is passed through the smart card. Entitlement data that is descrambled and used in the smart card for functions such as key generation is re-inserted in scrambled form in the high speed output data signal from the smart card. A variable delay device is included in the smart card for controlling when scrambled entitlement data is re-inserted into the data stream. Varying the delay permits establishing a desired timing relationship between the reinserted data and other data …
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed August 4, 1995 and granted April 4, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 4, 2015.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 4, 2017.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.