The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 20, 2007
Filed:
Jan. 27, 2003
David B. Cross, Redmond, WA (US);
Jianrong Gu, Bellevue, WA (US);
Josh D. Benaloh, Redmond, WA (US);
Thomas C. Jones, Sammamish, WA (US);
Paul J. Leach, Seattle, WA (US);
Glenn D. Pittaway, Woodinville, WA (US);
David B. Cross, Redmond, WA (US);
Jianrong Gu, Bellevue, WA (US);
Josh D. Benaloh, Redmond, WA (US);
Thomas C. Jones, Sammamish, WA (US);
Paul J. Leach, Seattle, WA (US);
Glenn D. Pittaway, Woodinville, WA (US);
Microsoft Corporation, Redmond, WA (US);
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.