Patent ID: 8204214

Claim:
A method for generating a data transaction ID for an interaction between first and second data units, the method comprising: the first data unit, by operation of a hardware processor, generating a first data item as a function of a first time data element, the first time data element being representative of a first time value associated with the generating of the first data item, and transmitting the first data item to the second data unit; the second data unit generating a second data item as a function of the received first data item and transmitting the second data item to the first data unit; the first data unit generating, by the hardware processor, a third data item as a function of the second data item and a second time data element, the second time data element being representative of a second time value associated with the generating of the second time data element, wherein the third data item comprises a transaction ID unique to the interaction between the first and second data units, and the first data unit associating and storing in a memory a first data unit identification code, a second data unit identification code, and the first and second time values with the generated transaction ID; wherein the generation of the first and third data items are functions of a first secret data value unique and secret to the first data unit and the generation of the second data item is also a function of a second secret data value unique and secret to the second data unit.