The newly introduced signature procedure is set to upgrade the bank’s security procedures to meet the needs of its business and corporate clients whose extensive payment transaction activities require a procedure which enables a large number of transactions to be approved in online banking. For the Postbank BestSign signature procedure, the client needs his account number and the online PIN and a small handheld USB device which serves as the hardware.

In a similar way to the mobileTAN and chipTAN procedure, Postbank sends the transaction data such as the recipient’s account number and the amount to the USB device which is connected to the customer’s PC. After the USB device has received the data, it displays the recipient’s account number and the transfer amount on the display of the USB device. Then, the client has to check the accuracy of this data before approving the payment transfer by pressing the USB button. Once the button is pressed, the chip inside the USB device generates a digital signature which replaces the client’s personal signature. The exchange of data between the device and Postbank is fully encrypted. Every employee authorized to sign payment transfers in the company requires his  own US device.

Source: The Paypers.com