Program-controlled selective line connection for chip card terminal

摘要

The method establishes a link between an authorised chip card terminal (2) and a central data processing installation (5) or network operator (4). Mutual authentication by exchange of unencrypted and encrypted random values is used, and a check is made on a terminal identification code. Measures are taken to prevent double debiting of the amount stored in the card. Payment data buffer-stored at the terminal are not erased until after an acceptance test.