Fraud Protection for Card Transactions

摘要

The method for use in authorising a card transaction for a particular card involves pre-storing several pieces of information supplied by a person authorised use the card. A piece of information, selected at random from one of the pieces of pre-stored information is requested from the person engaged in a card transaction. The information being requested is indicated in the request by a description of its nature so that the correct response can not be deduced from the request without knowing the pre-stored information. The transaction is completed only if the requested information is correctly supplied. Preferably, the request is made secretly to the person. The information is selected so that the same piece of information is not selected for two successive requests.