Enciphered communication system
US5574785A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 29, 1994 |
| Grant date | Nov 12, 1996 |
| Priority date | — |
| Expiry date | Dec 29, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/34
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
An enciphered communication system is provided which has a plurality of cipher keys selectively used for enciphering data, wherein even when a cipher key number used at a transmitting side is not correctly transmitted to a receiving side, the receiving side can change the cipher key to a correct one. A transmitter has appendant data affixing means for affixing appendant data to information to be enciphered, and a receiver has appendant data detecting means for detecting the appendant data from deciphered data, and cipher key determining means for successively changing the cipher key of the receiver when the appendant data is not accurately detected. Consequently, when the cipher key is changed, for example, the receiving side itself can restore data even if the cipher key number is not correctly transmitted thereto.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.