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. 12, 1986
Filed:
Nov. 10, 1983
Carl M Campbell, Jr, Newtown Square, PA (US);
VISA U.S.A. Inc., San Mateo, CA (US);
Abstract
The subject invention relates to a new and improved key management system particularly suited to facilitate communication between point of sale terminals and a host processor. The system provides for the generation of a table of keys in the terminal. The terminal includes a counter which is related to the table of keys. During a transaction, information, such as a personal identification number (PIN) is encrypted using one of the keys in the table. This information is transmitted, along with other transaction data, and the number stored in the counter. By utilizing the information in the counter, the host processor can generate the key used for encrypting the PIN. By this arrangement, security is enhanced and there is no need for large storage of keys at the central host.