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. 02, 1995
Filed:
Mar. 26, 1993
Kent D Rager, Elgin, IL (US);
Steven H Lay, Elgin, IL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
An encryption code and at least one key are provided to a secure transmission device, via an external keying device, and stored in a volatile memory. A user code, entered via a keypad by a user, is received by the secure transmission device. An encrypted representation of the at least one key, based on the encryption code and the at least one key, is generated and stored in a non-volatile memory. Also, an encrypted representation of the encryption code and the user code, based on the user code, are generated and stored in the non-volatile memory. Upon power down of the secure transmission device, the at least one key and encryption code stored in the volatile memory are erased.