An algorithm to create and validate a one time password
CA 2583741 C · Owner: Verisign, Inc. · Inventors: Hart, Loren; M'Raihi, David; Popp, Nicolas
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A token calculates a one time password by generating a HMAC-SHA-1 value based upon a key K and a counter value C, truncating the generated HMAC~-SHA-1 value modulo 10~Digit, where Digit is the number of digits in the one time password. The one time password can be validated by a validation server that calculates its own version of the password using K and its own counter value C'. If there is an initial mismatch, the validation server compensate for a lack of synchronization between counters C and C' within a look-ahead window whose , size can be set by a parameter s.
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 October 17, 2005 and granted October 14, 2014. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 17, 2025.
- Certificates of supplementary protection extend only drug patents, and it isn't classified as one.
- 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.