US Patent 7309006 Settlement terminal

To prevent skimming of card data used in electronic payment, attention is given to a phenomenon occurring in performing the fraudulent act of attaching a skimmer to a settlement terminal—namely that the settlement terminal is turned on and off several times. Detected power-on/off abnormalities are determined in accordance with an abnormal power-on/off definition stored in a memory. This may, for example, be that when the number of times the settlement terminal is turned on or off within a specified time period exceeds a predetermined number, the power-on/off is defined as abnormal power-on/off. When the power-on/off is determined to be abnormal, warning information is sent to a settlement organ computer.