[Printers] HP Color Laserjet 2500 Results

[Seth David Schoen]

Michael Sleator writes:

> It strikes me as interesting that the machines identified thus far
> that use the "tosky" code are rather different beasts (if we lump
> all of the HPs together).  The Toshiba FC-22 is a US$40k (with EFI
> controller) production printer/copier with a four drum, laser-based
> print engine.  The Kyocera C5016N is a US$2k small-office printer
> with an LED-based single drum print engine, and the HP 2500 (US$1100)
> & 2600N (US$400) are home/small-office printers with laser-based
> single drum print engines.
> 
> [...]
> 
> All of this suggests that either these machines use some common
> low-level controller chip which imbeds the forensic codes, or
> there's been some effort toward uniformity in the codes.  It would
> be interesting to build a database of makes/models that use each
> coding scheme.  This might yield some insight into the business
> and politics behind it all.

I agree.  One possibility is that Xerox first came up with some version
of the 15x8 code (with some reserved columns?) and then the Secret
Service suggested that other manufacturers use it unless they wanted to
go to the trouble of creating their own codes.

I'm still waiting for some information on professional scanning services
to which we might outsource the scanning of our probably thousands of
sheets of print samples.  That would make it a lot more convenient to
go through and try to classify the codes.

Otherwise, I may go through them by hand and take some notes on which
codes look alike.  We clearly need that information eventually.

-- 
Seth Schoen
Staff Technologist                                schoen at eff.org
Electronic Frontier Foundation                    http://www.eff.org/
454 Shotwell Street, San Francisco, CA  94110     1 415 436 9333 x107