Prevention of determination of time of execution of predetermined data processing routine in relation to occurrence of prior observable external event
CA 2037857 C · Owner: Anderson, Steven Edward · Inventors: Hart, Steven Raney; Anderson, Steven Edward; Griffin, Roy Allen, Iii
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Compromise of a predetermined secure data processing routine by a procedure known as a "clock attack" is prevented by a method that inhibits synchronization with, externally generated instructions by preventing determination of the time of execution of, the predetermined data processing routine in relation to occurrence of an externally, observable event that precedes the execution of the predetermined routine. The method, includes the step of (a) randomly varying the duration between the occurrence of the, externally observable event and the execution of the predetermined routine. Step (a), includes the steps of (b) executing one or more interim data processing routines between, the …
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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 March 8, 1991 and granted January 16, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 8, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 8, 2013.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.