Deriving a symmetric key from an asymmetric key for file encryption or decryption
US7181016B2 · kind B2 · utility
50Cited by
30References
19Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 27, 2003 |
| Grant date | Feb 20, 2007 |
| Priority date | — |
| Expiry date | Jun 10, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L63/0823
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
One aspect relates to a process and associated device that provides a private key of an asymmetric key pair in a key device. A symmetric master key is derived from the private key of the asymmetric key pair. The symmetric master key is stored in a computer memory location. The symmetric master key is used to encrypt or decrypt a file encryption key. The file encryption key can encrypt or decrypt files. In another aspect, the user can still access the files even if a user deactivates the key device by encrypting or decrypting the file encryption key directly from the symmetric master key.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.