Strengthened public key protocol
US5933504A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 17, 1996 |
| Grant date | Aug 3, 1999 |
| Priority date | — |
| Expiry date | May 17, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F7/725
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A cryptosystem utilizes the properties of discrete logs in finite groups, either in a public key message exchange or in a key exchange and generation protocol. If the group selected has subgroups of relatively small order, the message may be exponentiated by a factor of the order of the group to place the message in a subgroup of relatively small order. To inhibit such substitution, the base or generator of the cryptosystem is chosen to be a generator of a subgroup of prime order or a subgroup of an order having a number of relatively small divisors. The message may be exponentiated to each of the relatively small divisors and the result checked for the group identity. If the group identity is found, it indicates a vulnerability to substitution and is rejected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.