Digital signature system, digital signature method, digital signature mediation method, digital signature mediation system, information terminal and storage medium
US6990585B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 15, 2001 |
| Grant date | Jan 24, 2006 |
| Priority date | — |
| Expiry date | Aug 16, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/68
- WIPO fieldIT methods for management
- WIPO sectorElectrical engineering
Abstract
The present invention provides digital signature techniques using an information terminal, such as a portable terminal, having limited calculation resources. In one embodiment, a signature demandant generates a document to be signed, and an agent receives this document. The agent generates summary text for this document, and transmits the summary text to a signatory, and the signatory displays the summary text using his or her information terminal. The signatory confirms the contents, employs a private key stored in his or her terminal to sign (encrypt) the summary text. The signatory thereafter transmits a signature value to the agent, who generates a signed document that includes the signature value. Finally, the signature demandant verifies (decrypts) the received signed document using the public key of the signatory and confirms the contents.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.