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. 12, 1987
Filed:
Oct. 30, 1985
Adrianus H Dieleman, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
A cryptographic validation for an external station of a communication system provided with a central data processing device, a number of access stations which are coupled thereto and a number of external stations which can be selectively coupled to the access stations. To validate an external station, the access station transmits a message encoded by a first encoding key. The external station decodes the message received and re-encodes the message using a second encoding key, transmitting the re-encoded message back to the access station. The access station then decodes this message using a second key decoder. This decoded data is compared with the data originally encoded by the access station. If the data is identical, the external station is validated.