Patent ID: 8199339

Claim:
A printing system comprising: a printer; a reading unit that reads a paper fingerprint of a paper sheet; a first controller that implements control for, when receiving a print instruction containing a document identifier which identifies document data to be printed causing the reading unit to read the paper fingerprint of the paper sheet used for printing and transmitting, to an upper device which is an origin of the document data, a request for a document containing paper fingerprint information and the document identifier, the paper fingerprint information being determined based on the read paper fingerprint; a second controller that implements control for, when printing, by the printer, document data containing the paper fingerprint information received from the upper device in response to the request for the document on the paper sheet, causing the reading unit to read the paper fingerprint of the paper sheet used for printing and, if the read paper fingerprint and the paper fingerprint indicated by the paper fingerprint information contained in the document data match, causing the printer to start a print process of the document data, and, if the read paper fingerprint and the paper fingerprint indicated by the paper fingerprint information contained in the document data do not match, inhibiting printing of the document data by the printer; and a third controller that implements control for, when the second controller causes the printer to start the print process of the document data, monitoring execution of the print process by the printer, and, if failure of the print process is detected by the monitoring, canceling the print process, causing the reading unit to read a paper fingerprint of a new paper sheet after the printer returns to a normal state, and transmitting, to the upper device, a new request for the document containing paper fingerprint information and the document identifier, the paper fingerprint information being determined based on the read paper fingerprint, wherein the second controller implements control for, when printing, by the printer, new document data containing the paper fingerprint information received from the upper device in response to the new request for the document on the paper sheet, causing the reading unit to read a paper fingerprint of a paper sheet used for printing and, if the read paper fingerprint and the paper fingerprint indicated by the paper fingerprint information contained in the new document data match, causing the printer to start a print process of the new document data, and, if the read paper fingerprint and the paper fingerprint indicated by the paper fingerprint information contained in the document data do not match, inhibiting printing of the new document by the printer, and wherein the upper device registers the document data into a database as an entry and returns a receipt number to a user, once notification is received that printing completed normally, the upper device deletes the entry from the database.