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:
Aug. 31, 1993
Filed:
Feb. 01, 1991
Applicant:
Inventor:
Michael W Bright, Arlington Heights, IL (US);
Assignee:
Motorola, Inc., Schaumburg, IL (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04L / ; H04K / ;
U.S. Cl.
CPC ...
380 21 ; 380 30 ; 380 43 ; 380 44 ; 380 45 ; 380 47 ;
Abstract
A method for recovering from encryption key variable loss, either inadvertent or the result of tampering. A predetermined key encryption key is encrypted with itself at the time when keys are first loaded, and the resultant key loss key is stored in non-volatile memory. This key loss key acts as a key encryption key for decryption of new shadow and traffic keys.