CSC 379 SUM2008:Week 4, Group 4
What if every page you print from a color printer were labeled with a hidden code, detailing the printer the page was printed from, the date of printing and the time of printing, down to the minute? What if this feature was intentionally hidden from the user and could not be disabled? What if the code could be viewed and decoded by anyone, not just law enforcement? These hidden tracking codes exist – examine the ethical considerations they pose. Should users be informed of the feature? Should users be able to disable the feature? Develop ethical arguments for both positions.
Printer Tracking Technology
How does it work?
Encoding data in the form a machine-readable printed graph is not a new idea—adhering printed barcodes to physical objects for tracking purposes has been a commercial practice since 1966, becoming truly ubiquitous in the 1980s. [1] Printer tracking codes are a lot like commercial UPC codes, except that they are virtually undetectable by unaided human eyes and data is encoded into a 2-Dimensional array of micro-dots. As an example, the Xerox DocuColor series printer encodes printer data into a 15x8 grid of nearly invisible yellowish dots. The grid is repeated across the entire page, so even fragmented documents may later be forensically identified. The data encoded by the printer is simple: the printer's serial number, the date and time at which a document was printed.
Currently, hidden printer tracking technology has been found only in some laser printers, of which EFF has compiled a non-comprehensive list.
Why Is It Useful?
Currently, the only official use of the hidden tracking dots by our government is their role in tracking down counterfeiters. These criminals often employ the technique of scanning legal currency, then by using a color laser printer or color laser copier, they are able to mass-produce the counterfeit bills that are of a high enough quality that they will fool most people. By using the hidden tracking codes, law-enforcement officials, specifically the Secret Service, are able to determine the brand and model number of the printer that produced the counterfeit bills as well as finding the specific serial number of the offending machine. They are then able to use that information to contact the manufacturer of the printer to gain determine who purchased that specific device.
Counterfeiters are not the only ones affected by this technology. By employing similar criminal techniques, document forgers are using color printers to forge driver's licenses, passports, and checks. By analyzing the tracking dots, authorities are able to create a paper trail leading to the forgers and expedite their capture.
This practice is not limited the the United States government as the governments of other countries concerned with the circulation of counterfeit currency also employ the same techniques used by the Secret Service.