Method and apparatus for changing the master key in a cryptographic system
US4972472A · kind A · utility
103Cited by
6References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 15, 1985 |
| Grant date | Nov 20, 1990 |
| Priority date | — |
| Expiry date | Mar 15, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L9/0894
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for changing the key in a cryptographic system or device are disclosed. A memory contains three storage areas for pending, active, and retired keys. New keys are loaded into the pending storage area. The key is changed by shifting the pending key into the active storage area and shifting the active key into the retired area for use by applications which have not been made aware of the key change. When an application presents a retired key, use of the retired key is allowed and the new key is returned to the application.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.