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:
May. 16, 1995
Filed:
Dec. 20, 1993
Roland A Merrick, Worchestershire, GB;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A cryptographic system includes a conventional DES facility for encrypting data using a key of N (=56) bits. The user however need only supply a first key of n bits, which is passed to a key management system. The key management system generates a second key of length N-n bits, which is combined with the first key to produce a full-length key of N bits. This full-length key is then passed to the DES facility to allow data to be encrypted and saved in a data store in the conventional manner. The value of n can be controlled such that if the user forgets the first key, it can be located in a reasonable time on a simple trial and error basis, thereby allowing retrieval of the encrypted data.