Showing papers by "Visa Inc. published in 1993"

Adaptive communication system within a transaction card network

Abstract: The present invention is a point-of-presence device installed in a merchant establishment as an interface between a retail information system and a transaction card authorization network. By using a simple message data format between the retail information system and the device, the device insulates the retail information system from changes to local communication access methods and changes to point-of-sale compliance requirements initiated by the card processor. The device first establishes a dial-up telephone connection to the authorization network and then interleaves both financial data messages and non-financial messages over the same telephone line to the authorization network. The device provides authorization response times that substantially equal response times provided by leased line connections to the authorization network. In addition, the present invention provides improved diagnostic and draft capture capability for the retail information system.

Account file for off-line transaction authorization

Abstract: An approach for handling data representative of invalid transaction cards is disclosed. A memory area 34 in a transaction terminal 16 is divided into a plurality of stacks. Two digits of the invalid account number are used to identify the stack into which the remainder of the account number is added. Stack start pointers are provided for file management. As the newest entries are added to the list, the oldest entries are purged. The subject system allows a large number of accounts to be stored in a minimum of space. Updates of the file can be easily handled during direct communication sessions between a central processor 12 and the terminal 16.