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:
Jan. 14, 1992
Filed:
Aug. 31, 1990
Lucina L Green, Verbank, NY (US);
Michael J Kelly, Poughkeepsie, NY (US);
Ronald M Smith, Wappingers Falls, NY (US);
Julian Thomas, Poughkeepsie, NY (US);
Phil C Yeh, Poughkeepsie, NY (US);
International Business Machines Corp., Armonk, NY (US);
Abstract
A facility for making dynamic changes to a system master key without stopping the system, and without loss of integrity to ongoing cryptographic operations. A version number is generated and associated with the current master key. A dynamic change is made to the master key, resulting in the then current master key becoming the old master key, and a 'new' current master key (with a new version number) being placed into operation. Subsequent cryptographic requests using a supplied key enciphered under the old master key are identified by means of a supplied version number associated with the supplied key. This identification triggers a reencipher operation, reenciphering the supplied key under the now current master key--after which the cryptographic operation proceeds. Unique patterns are generated to verify the contents of the master key registers, and to authorize normal use of the cryptographic facility, and issuers of key-change operations.