Segmented secret-key storage system, segment storage apparatus, segmented secret-key storage method
US9894056B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 16, 2014 |
| Grant date | Feb 13, 2018 |
| Priority date | — |
| Expiry date | Nov 6, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L63/0876
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
The risk of leakage of secret information caused by leakage of a secret key is reduced. A segmented secret-key storage system segments a secret key SK into segments that can be combined at the time of decryption or at the time of generation of a signature and records the secret-key segments sk1, . . . , skN in segment storage apparatuses. The secret-key segments are changed, periodically or under a predetermined condition, to another set of secret-key segments that satisfies a condition for combination. In the segmented secret-key storage system, the secret key SK is not revealed unless the secret-key segments are stolen from all the segment storage apparatuses in an interval between changes made to the secret-key segments. Accordingly, the risk of leakage can be greatly reduced in comparison with the risk of leakage of the secret key from a single apparatus.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.