One time password
US8087074B2 · kind B2 · utility
21Cited by
12References
15Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 17, 2005 |
| Grant date | Dec 27, 2011 |
| Priority date | — |
| Expiry date | Apr 2, 2027 |
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.