Key variable generator for an encryption/decryption device
US4369332A · kind A · utility
41Cited by
3References
29Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 26, 1979 |
| Grant date | Jan 18, 1983 |
| Priority date | — |
| Expiry date | Sep 26, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/125
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
An apparatus and method for generating a unique working key variable for controlling the operation of an encryption/decryption device during each user specified time period. The apparatus generates each working key variable by encrypting a user specified value, unique for each specified time period, under control of a fixed key variable stored in the apparatus. After the user specified value has been encrypted, the apparatus utilizes the encrypted (working) key variable to control the encryption/decryption of data during the corresponding user specified time period.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.