Transparently securing data for transmission on financial networks

Abstract

Systems and methods for performing financial transactions are provided. In one embodiment, the invention provides a method for processing token data for a bank card transaction, the method includes: receiving a string of first token data from a token at a token reader; modifying the first token data and generating second token data, the second token data including modified token data; performing a modulo arithmetic operation on the second token data and determining a mod 10 check digit that will cause a modulo arithmetic check of the second token data to yield the same result as the modulo arithmetic check would yield on the first token data; and inserting the mod 10 check digit in the second data string and forwarding the second data string for the transaction.

1 - 15 . (canceled) 
     
     
         16 . A method for processing token data for a purchase transaction, the method comprising:
 a terminal receiving a first set of token data from a token;   the terminal encrypting selected characters of the token data;   the terminal replacing the original selected characters of the token data with the encrypted selected characters of the token data creating a second set of token data;   performing a modulo calculation on the second set of token data and determining a check digit that when inserted into the second set of token data will cause a modulo arithmetic check of the second set of token data to yield the same result as the modulo arithmetic check would yield on the first set of token data; and   inserting the check digit in the second data set to create a third data set; and   forwarding the third data set to a transaction processing entity.   
     
     
         17 . The method of  claim 16 , wherein the second set of token data comprises a string of encrypted token data and original unencrypted token data assembled in the same format as the first set of token bank data. 
     
     
         18 . The method of  claim 16 , wherein the check digit is appended to the second set of token data or replaces a character in the second set of token data. 
     
     
         19 . The method of  claim 16 , wherein the check digit is added to the second set of token data at a predetermined location of the second set of token data. 
     
     
         20 . The method of  claim 19 , wherein the predetermined location is one position prior to the last four digits of an account number. 
     
     
         21 . The method of  claim 16 , wherein the check digit is added to the second data set at a predetermined location of the second data string and an digit in the first data set remains unchanged in the second data set. 
     
     
         22 . The method of  claim 16 , wherein the first set of token data is track data from a track of the token. 
     
     
         23 . The method of  claim 16 , wherein the first set of token data is PAN data from a token. 
     
     
         24 . The method of  claim 16 , wherein the encrypting selected characters comprises converting the selected characters to eight bytes, and performing a triple DES encryption on the selected token data. 
     
     
         25 . The method of  claim 16 , wherein the encrypting selected characters comprises and creating a second set of token card data comprises:
 converting X digits of the first set of token to a predetermined number of Y bytes; and   performing a Y-byte encryption on the converted token data; and   converting the encrypted Y bytes of encrypted data to X digits.   
     
     
         26 . The method of  claim 16 , wherein performing the modulo arithmetic and inserting the check digit comprises performing a modulo calculation on the X digits to determine the check digit and inserting the check digit in the appended predetermined digit. 
     
     
         27 . The method of  claim 16 , wherein the token data that is encrypted is a subset of the original token data string, and the encrypted token data replaces the original token data at the same location or locations in the string. 
     
     
         28 . A method for securing token data from a token presented for a purchase transaction, the method comprising:
 a point of sale token reader receiving the token data from the token for the purchase transaction, wherein the token data comprises clear text token data read from the token at the point of sale, and the clear text token data include a mod  10  check digit;   creating secured transaction data by selectively encrypting a first portion of the clear text token data such that a second portion of the clear text token data remains unencrypted in order to traverse the transaction processing network, the second portion including the mod  10  check digit;   altering the encrypted first portion such that the mod  10  check digit remain valid for the secured transaction data; and   forwarding the secured token transaction data to the transaction processing network for the purchase transaction.   
     
     
         29 . The method of  claim 28 , wherein the last four digits of the second portion remain as clear text to maintain compatibility with purchase transaction receipt printing. 
     
     
         30 . The method of  claim 28 , wherein an expiry date within the second portion remains as clear text to maintain compatibility with point of sale date checking. 
     
     
         31 . The method of  claim 28 , wherein a bank identification number within the second portion remains as clear text to maintain compatibility with a point of sale network requirement. 
     
     
         32 . The method of  claim 28 , wherein a portion of a bank identification number within the second portion remains as clear text to maintain compatibility with a point of sale network requirement.