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:
Jul. 20, 1993
Filed:
Sep. 30, 1992
Douglas A Hardy, Mesa, AZ (US);
Leslie K Lewis, Scottsdale, AZ (US);
Barry N Altschuler, Scottsdale, AZ (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
An apparatus for secure communications contains a controller for automatically selecting one of several data ciphering devices utilizing one of a plurality of ciphering algorithms common to transmitting and receiving terminals. A transmitter for transmitting encrypted data, and a receiver for receiving encrypted data are coupled to the plurality of ciphering devices. The controller automatically determines which of the ciphering devices to employ for any given secure communication. The method for establishing a secure communications link includes the steps of exchanging a first message for determining a common key generation and ciphering method and comparing a further shared message for validation of communications terminal security. Additionally, the steps of trading a still further message for providing data to form traffic keys to initialize key generators, interchanging an additional message for synchronizing and verifying synchronization of secure communications between secure communications terminals, and initiating secure communication are used.