an apparatus comprises a data display unit which causes a display device to output display data that indicates a drawing screen complying with the display request, a reliability decision unit which decides a legality of a transmission source of the display request, and which makes an output request for information capable of confirming a reliability of the display data that the data display unit causes the display device to output, on the basis of a result of the decision, and an output unit which outputs the information capable of confirming the reliability of the display data as complies with the output request from the reliability decision unit, separately from the display data that is caused to be outputted by the data display unit.