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. 15, 1990
Filed:
Nov. 30, 1988
Applicant:
Inventors:
Mark G Spiotta, Algonquin, IL (US);
Erling Bjerga, Elmhurst, IL (US);
Assignee:
Motorola, Inc., Schaumburg, IL (US);
Primary Examiner:
Int. Cl.
CPC ...
H04K / ; H04L / ;
U.S. Cl.
CPC ...
380-2 ; 380 44 ; 380 47 ;
Abstract
An encryption key, required to encrypt and decrypt data according to a predefined algorithm is usually retained in a volatile memory device. Detection of loss of the key or corruption of the key is frequently possible only be means of the encryption circuit itself testing the key. Automated and repetitive testing of encryption keys by means of a processor or a control circuit periodically requesting the encryption circuit to test an encryption key minimizes data loss and system down time due to corrupted or lost keys.