Exponentiation cryptographic apparatus and method
US4424414A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 1, 1978 |
| Grant date | Jan 3, 1984 |
| Priority date | — |
| Expiry date | May 1, 1998 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L9/3066
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A cryptographic system transmits a computationally secure cryptogram that is generated from a secret transformation of the message sent by the authorized transmitter; the cryptogram is again transformed by the authorized receiver using a secret reciprocal transformation to reproduce the message sent. The secret transformations use secret cipher keys that are known only by the authorized transmitter and receiver. The transformations are performed with nonsecret operations, exponentiation, that are easily performed but extremely difficult to invert. It is computationally infeasible for an eavesdropper either to solve known plaintext-ciphertext pairs for the secret cipher keys, or to invert the nonsecret operations that are used to generate the cryptogram.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.