Encryption apparatus, decryption apparatus, expanded key generating apparatus and method therefor, and recording medium
US7194090B2 · kind B2 · utility
31Cited by
9References
24Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 12, 2001 |
| Grant date | Mar 20, 2007 |
| Priority date | — |
| Expiry date | Aug 7, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/24
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Expanded key schedule circuit for common key encryption system in which expanded keys are used in a predetermined order in data randomizing process for encryption and in a reversed order in data randomizing process for decryption, comprises round processing circuits connected in series. The round processing circuits subject the common key or sub key of a previous stage to a round function to output a sub key. The sub key of the last stage is equal to the common key. The expanded keys are generated from the sub keys.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.