AN IMPROVED METHOD AND SYSTEM FOR CONDUCTING SECURE PAYMENTSOVER A COMPUTER NETWORK

摘要

A method is provided for conducting a financial transaction by a purchaser with a merchant having an acquirer bank, over a communications network. The method includes the steps of sending a first authorization request using a pseudo account number associated with a real account number to a service provider which forwards a second authorization request to the issuer using t he real account number and preferably a pseudo acquirer code associated with th e service provider such that the response to the second request is based on th e real account number and sent back to the service provider who preferably forwards a response to the first request preferably to the "real" acquirer. A message authentication code is further provided which includes transaction data, and where the authorization request if formatted as a standard payment card track having one or more fields including a discretionary field in whic h the message authentication code is placed.