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:
Dec. 09, 2003
Filed:
Oct. 28, 1999
William F. Price, III, Los Altos, CA (US);
PGP Corporation, Palo Alto, CA (US);
Abstract
One embodiment of the present invention provides a system that facilitates encrypting and decrypting a data item. The system operates by encrypting a data item with a session key using a symmetric encryption mechanism to produce an encrypted data item. Next, the system splits the session key into a plurality of shares so that the session key can be reconstituted from a predefined number of shares. The system also receives a plurality of responses from the user (which may be responses to questions), and encrypts the plurality of shares with the plurality of responses using the symmetric encryption mechanism to generate a plurality of encrypted shares. The plurality of encrypted shares are stored for later retrieval. In one embodiment of the present invention, the system decrypts the data item by, receiving a plurality of new responses from the user, and attempting to decrypt the plurality of encrypted shares with the plurality of new responses. Note that a share will be successfully decrypted if a new response matches a response that was previously used to encrypt the share. If the predefined number of shares are successfully decrypted, the system uses the successfully decrypted shares to reconstitute the session key, and then uses the session key to decrypt the encrypted data item.