EP0804003A3
Digital signature method and communication system
Abstract
A system for enabling verified or verifiable communications while maintaining anonymity, in which a common public parameter, such as a prime number, and a registered signature are changed, respectively, by a specifier and a signer to provide a digital signature which accompanies a message sent from the signer to a verifier.
Term
Term ended
Projected expiry passed 25 April 2017, 9.4 years ago.
- Priority
- Filed
- Published
- Projected expiry
- Today
1 sheet
Sheet 1
Every citation, both waysCites: the store holds 0 of 1
| Reference | Relation | Cited during |
|---|---|---|
| LEE W -B ; CHANG C -C: "Efficient group signature scheme based on the discrete logarithm", IEE PROC., COMPUT. DIGIT. TECH., vol. 145, no. 1, 1 January 1998 (1998-01-01), UK, pages 15 - 18, XP002146085, ISSN: 1350-2387 | Non-patent | Search report |
| CHAUM D ; VAN HEYST E: "Group signatures", EUROCRYPT '91, SPRINGER-VERLAG, 8 April 1991 (1991-04-08) - 11 April 1991 (1991-04-11), Berlin, Germany, pages 257 - 265, XP000900793, ISBN: 3-540-54620-0 | Non-patent | Search report |
| SCHNEIER, BRUCE: "Applied cryptography; Second Edition", 1 January 1996, JOHN WILEY & SONS, INC., USA, ISBN: 0-471-12845-7, XP002146086 | Non-patent | Search report |
| TATSUAKI OKAMOTO: "A DIGITAL MULTISIGNATURE SCHEME USING BIJECTIVE PUBLIC-KEY CRYPTOSYSTEMS", ACM TRANSACTIONS ON COMPUTER SYSTEMS,US,ASSOCIATION FOR COMPUTING MACHINERY. NEW YORK, vol. 6, no. 4, 1 November 1988 (1988-11-01), pages 432 - 441, XP000001601, ISSN: 0734-2071 | Non-patent | Search report |
6 members in 3 offices
Priority claims8
| Document | Office | Kind | Date |
|---|---|---|---|
| 10822596 | Japan | A | |
| 10822596 | Japan | – | |
| 10822696 | Japan | A | |
| 10822696 | Japan | – | |
| 10822596 | – | – | – |
| 10822696 | – | – | – |
| JP19960108225 | – | – | – |
| JP19960108226 | – | – | – |
Members6
| Document | Office | Kind | |
|---|---|---|---|
| EP0804003A2 | European Patent Office (EPO) | A2 | |
| JPH09298536A | Japan | A | |
| JPH09298537A | Japan | A | |
| EP0804003A3This record | European Patent Office (EPO) | A3 | |
| US6154841A | United States of America | A | |
| JP3513324B2 | Japan | B2 |
8 legal events, as the office reported them to INPADOC
Over the term
Point at a mark for the eventEvents
| Event | Code | |
|---|---|---|
| Application withdrawnWithdrawn18W | 18W | |
| Information on the status of an ep patent application or granted ep patentGrantedSTATUS: THE APPLICATION HAS BEEN WITHDRAWNSTAA | STAA | |
| First examination report despatched17Q | 17Q | |
| Request for examination filed17P | 17P | |
| Designated contracting statesAK | AK | |
| Search report despatchedORIGINAL CODE: 0009013PUAL | PUAL | |
| Designated contracting statesAK | AK | |
| Public reference made under article 153(3) epc to a published international application that has entered the european phaseORIGINAL CODE: 0009012PUAI | PUAI |
Numbers
- Publication
- 0804003
- Publication, DOCDB
- 0804003
- Publication, EPODOC
- EP0804003
- Application
- 97302857
- Application, DOCDB
- 97302857
- Application, EPODOC
- EP19970302857
Titles3
- German
- Verfahren zur digitalen Unterschrift und Kommunikationssystem
- English
- Digital signature method and communication system
- French
- Procédé de signature numérique et système de communication
Classification
- CPC, 4
- H04L9/3218
- H04L9/3013
- H04L9/3255
- H04L2209/42
- IPC, 1
- H04L9 32
Designated states1
- Contracting states, 1
- United Kingdom