Patent ID: 8253952

Claim:
An image forming apparatus which prints out a print job received through a network, wherein the print job includes print data and attribute information indicating print settings of the print data, the apparatus comprising: an acquisition device that acquires limiting information as packets through the network with the reception of the print job, wherein the limiting information is used to limit the print settings indicated by the attribute information in the print job when the image forming apparatus prints out the print job, and is managed in a print system to which the image forming apparatus belongs; a verification device that verifies digital signature information included in packets containing the limiting information acquired by said acquisition device, wherein the digital signature information is for guaranteeing that an issuer of the limiting information is authorized and the limiting information is not rewritten by fraudulent means when in transit; a control device that controls to print out, if the attribute information in the print job indicates the print settings not to be limited by the limiting information, the print job in accordance with the attribute information in the print job, and print out, if the attribute information in the print job indicates the print settings to be limited by the limiting information, the print job with print settings different from the print settings indicated by the attribute information in the print job in accordance with the limiting information acquired by said acquisition device; and a setting device that sets a policy to disable printing of a print job without the limiting information, wherein each of the packets containing the limiting information include a header including codes indicating the limiting information, wherein the limiting information designates at least double-sided printing setting, monochrome printing setting, N-up printing setting (N≧2), or combinations thereof, for limiting the print settings indicated by the attribute information, and wherein, when the verification of the digital signature information included in a particular packet of the packets by said verification device is successful, said control device controls to store the limiting information in a storage unit so that said control device prints out in accordance with the limiting information, and when the verification of the digital signature information included in the particular packet by said verification device is unsuccessful, said control device controls to abandon the packets.