Digital Signature on Transaction Amount in Point of Sale
Original Publication Date: 1985-Aug-01
Included in the Prior Art Database: 2005-Feb-19
This article discloses a method of obtaining digital signatures on transaction amount data in a point-of-sale network. The method is, for many purposes, a variation on, and is a more efficient procedure than, the digital signature method disclosed in the article on pages 1109- 1122. Referring now to the previous article, there is disclosed a method of digital signatures involving a customer's smart card, a retailer's terminal, and an issuing bank's host computer system in which the signature is composed of 1-keys and 0-keys where a 1-key is supplied for each 1 bit in the transaction amount B and each 1 bit in the complement of B and a 0-key is supplied for each 0 bit in B and each 0 bit in the complement of B. Therefore, the smart card provides the retailer's terminal with n' 1-keys and n' 0-keys, for a total of 2n' = n keys.