How Your Printer Leaves Invisible Tracking Codes on Every Page

Printers embed hidden yellow dots on pages, revealing who printed what and when. This monitoring tech, present for over 20 years, aids in stopping counterfeiting however raises privateness considerations.

Monitoring Codes in Element

For those who add a printer to Home windows 11, you may nonetheless be getting monitoring codes printed in your pages. Though you could possibly theoretically change the settings to regulate the privateness in Home windows 11, you possibly can’t change dots from going in your printed pages. Monitoring codes are a type of steganography that includes hiding data inside one other medium, corresponding to a picture or doc. Within the case of printers, monitoring codes are used to embed figuring out details about the printer and the printed doc inside the doc itself. Essentially the most well-known kind of printer monitoring code is the yellow dot sample, the place tiny, barely seen yellow dots are organized in a grid to encode knowledge.

Monitoring codes are sometimes created by the printer firmware and embedded within the doc as it’s being printed. The firmware comprises algorithms that generate the precise sample of dots or different steganographic markings based mostly on the printer’s figuring out data and the timestamp of the printing job. This course of is automated and doesn’t require any person intervention. The truth is, most customers do not even know their printers are printing data that may observe them.

How Did These Codes Come About?

Printer monitoring codes, often known as machine identification codes (MIC) or yellow dots, have been utilized by printer producers for the reason that mid-Nineteen Eighties. The patent for this expertise was initially granted in 1993 however has expired. The origin of printer monitoring codes could be traced again to the cooperation between the U.S. authorities and printer producers to forestall counterfeiting. Within the Nineteen Eighties, the U.S. Secret Service approached the Japanese Ministry of Finance to handle the problem of counterfeit currencies produced utilizing coloration copiers.In consequence, copier producers agreed to implement machine identification codes.

Printer producers have acknowledged that the first purpose for implementing monitoring codes is to help legislation enforcement in tracing the origin of counterfeit foreign money and different unlawful paperwork. Nonetheless, privateness advocates have expressed considerations in regards to the potential abuse of this expertise, because it allows the monitoring of people based mostly on the paperwork they print.

Regardless of the controversies surrounding printer monitoring codes, they proceed to be a typical function in most trendy printers. There was a listing of printers the place this stenography confirmed up, but it surely was final up to date in 2017 and hasn’t been stored working since then. The listing notes that the majority trendy laser printers have some type of steganography monitoring, even when they do not print yellow dots.

How Printer Monitoring Codes Perform

When somebody prints a sheet of paper on a coloration printer, a grid of 15 by 8 yellow dots is embedded inside the sheet. The grid is repeated all through the printed web page, and the grids are offset to make sure that every grid print does not run into one other. The grids are additionally parallel to the perimeters of the web page. The dots type a sequence of knowledge, very similar to punch playing cards used on the earliest computer systems.

The monitoring codes are encoded utilizing a binary system, the place every dot represents a bit of knowledge. The presence or absence of a dot at a particular location within the sample corresponds to a “1” or “0” in binary code. The dots are organized in a grid, and every row of the grid encodes a particular piece of knowledge, such because the printer’s serial quantity, manufacturing date, and the timestamp of the printed doc.

To decode the monitoring data, the printed web page is first illuminated with blue mild, which makes the yellow dots extra seen. The web page is then photographed or scanned at a excessive decision, sometimes 600 dpi or larger. The ensuing picture is processed utilizing specialised software program that analyzes the dot sample and converts it into binary code. The binary code is then translated into human-readable data based mostly on the recognized construction of the monitoring code grid.

If you may get the dots to indicate up, you possibly can doubtlessly learn what they encode. That is the information every row represents:

• The printer serial quantity is encoded in bytes 14, 13, 12, and 11 utilizing binary-coded decimal (BCD), with two digits per byte. It’s distinctive to every printer and stays fixed.
• Byte 15 is usually zero, however its worth could also be fixed for every printer and convey non-user-visible details about the printer’s mannequin or configuration.
• Byte 10 acts as a separator and sometimes consists of all ones. It doesn’t seem to encode any data.
• The yr the web page was printed (with out the century) is encoded in byte 8. For instance, the yr 2005 is coded as 5.
• The month and day the web page was printed are encoded in bytes 7 and 6, respectively.
• The hour the web page was printed is encoded in byte 5. This can be within the UTC time zone or set inaccurately inside the printer.
• The minute the web page was printed is encoded in byte 2.
• Bytes 9, 4, and three are unused.
• Byte 1 is a row parity bit, which is ready to make sure an odd variety of dots are current per row.

As a substitute of studying all of this data, if you wish to decode this, there is a useful web site that may try to course of the information and offer you a consequence.

Might This Function Be Abused?

Like many options put in for safety causes (like Microsoft’s upcoming Recall function), steganography can be utilized for nefarious functions. One of many foremost considerations is the shortage of transparency surrounding using monitoring codes. Many customers are unaware that their printed paperwork comprise hidden figuring out data, and printer producers haven’t at all times been forthcoming in regards to the presence or function of those codes.

The potential for misuse and abuse of printer monitoring codes is one other important concern. Whereas the expertise is meant to help legislation enforcement in investigating crimes corresponding to counterfeiting, there’s a threat that it might be used for different, much less official functions. For instance, monitoring codes might be used to watch and suppress political dissent, observe whistleblowers, or goal people based mostly on their beliefs or associations.

It is a important pink flag for any particular person who’s involved in regards to the privateness of their data. Its use in some instances to prosecute whistleblowers who’ve leaked paperwork is well-documented.

Can You Disable This Monitoring?

A Star Delta-10 dot matrix printer.

So far, it’s inconceivable to take away the doc monitoring dots until you resolve to print on a dot-matrix printer. The directions for printing these monitoring dots are embedded within the firmware for the printer. The one answer some folks have give you is printing on yellow paper to make the dots even much less seen. Nonetheless, below a blue LED mild, you may nonetheless see the gridlike patterns printed on each sheet. It is humorous that you would be able to even optimize Microsoft Edge for elevated privateness, however not your old-technology printer.

As of late, not many individuals use printed sheets for something aside from everlasting documentation. With a lot cloud storage out there to whoever needs it, it is unlikely that individuals will proceed utilizing printers on the similar scale that they did within the ’90s and early ’00s. Nonetheless, these dots nonetheless exist, and it does not take a rocket scientist to learn them. When printing one thing delicate, remember that the date and time of the doc are additionally recorded. It might be used to show the existence of a printed web page for time-specific points.