Decryption service providing device, processing device, safety evaluation device, program, and recording medium
US9735963B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 15, 2014 |
| Grant date | Aug 15, 2017 |
| Priority date | — |
| Expiry date | Mar 24, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L9/3013
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A private key is held which conforms to an ElGamal encryption system on a semigroup, calculation of an order of an element of the semigroup being computationally difficult, information corresponding to ciphertext conforming to the ElGamal encryption system is input, a private key s is used to decrypt the information corresponding to the ciphertext in conformance to the ElGamal encryption system, and information corresponding to a result of decrypting the ciphertext is obtained and output. Alternatively, whether it is computationally difficult or easy to calculate the order of the element of the semigroup is determined, and the safety of a decryption service providing device is evaluated based on the determination result.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.