Sonsivri

I am looking for idea: I need sniffer for USB printer
I would like to have box with usb connector, this box will save documents which is printed on external (USB) printer
After some time , connect this box to PC and see all documents which was printed!
Source is Android or any system.

is this printer networked ?
maybe connect via a dedicated computer, and tell it to keep all documents etc..
seem that a dedicated usb device could get complicated to do as project, as would need vast memory, or hard drive as storage..
or are you looking for file names only, then memory would be enough.
edit
maybe raspberry pi, or beaglebone black , and sd card for storage..

Since it is a printer, you can just look at the paper

You can also use this to save all your documents as PDFs, since it acts as if it was a printer (Broadgun pdfMachine - not my upload): http://rg.to/file/f86ef8ddc043748d52819977e4404ffa/

Unless of course, you are spying on people, which is not nice - at all

There is also the 'Print to file' option to be used with the printer chosen. This assumes you are in control of the print dialog though.

If this is for legitimate purposes there are plenty of commercially available print logging software packages out there, no need for an external hardware logging device...

I don't think that's an easy task.

Oldtimer's printers just receive the ASCII chars and print them using self contained fonts (or may be previously downloaded) so it's easy to sniff them.

To keep the price low, modern low cost printers often receive the whole bitmap already prepared by the printer drivers in PC (a lot of data). Higher quality printers will adhere to standards like PCL5, PCL6 or postscript.

Assuming that you manage to sniff and save all data traffics, you will have to filter non  printing data from this bit stream (ie handshake, status & error reports...), then to emulate the behavior of specific printer to see what are printed. 

He'll just play it back to another printer, same model, or perhaps the same printer after people have picked up their prints and gone home.

The handshaking, though, may make that next to impossible.

Even if well intended, which I somehow doubt, the possibility of such a device appearing in the wild is quite scary - the perfect tool for identity thieves and for industrial espionage...you go to a copy center, you print your stuff, you rightfully expect it to not have been recorded.

That said, I believe there are printer models with job buffers that you can recall. I've seen one, but don't recall the model (not USB, though).

As I said though, there is commercial software package out there that will archive all printed pages from a computer and allow them to be viewed later...  So if you are using a shared or compromised computer there might very well not be any privacy...

For example...   http://www.papercut.com/tour/print-archiving/