One time password
US8434138B2 · kind B2 · utility
6Cited by
14References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 6, 2011 |
| Grant date | Apr 30, 2013 |
| Priority date | — |
| Expiry date | Dec 6, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/20
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.