[Infowarrior] - Fingerprinting Blank Paper Using Commodity Scanners

[Richard Forno]

Fingerprinting Blank Paper Using Commodity Scanners
By Ed Felten - Posted on March 13th, 2009 at 7:30 am

Today Will Clarkson, Tim Weyrich, Adam Finkelstein, Nadia Heninger,  
Alex Halderman and I released a paper, Fingerprinting Blank Paper  
Using Commodity Scanners. The paper will appear in the Proceedings of  
the IEEE Symposium on Security and Privacy, in May 2009.

Here's the paper's abstract:

     This paper presents a novel technique for authenticating physical  
documents based on random, naturally occurring imperfections in paper  
texture. We introduce a new method for measuring the three-dimensional  
surface of a page using only a commodity scanner and without modifying  
the document in any way. From this physical feature, we generate a  
concise fingerprint that uniquely identifies the document. Our  
technique is secure against counterfeiting and robust to harsh  
handling; it can be used even before any content is printed on a page.  
It has a wide range of applications, including detecting forged  
currency and tickets, authenticating passports, and halting  
counterfeit goods. Document identification could also be applied  
maliciously to de-anonymize printed surveys and to compromise the  
secrecy of paper ballots.

More:

http://freedom-to-tinker.com/blog/felten/fingerprinting-blank-paper-using-commodity-scanners