Speckle My Papers

Imperial College London and Durham University have announced a low-cost method of uniquely identifying paper documents, plastic cards, product packaging, and the like. The process scans the surface with a laser to measure the amount of light reflection. The researchers offer this description:

Using the optical phenomenon of 'laser speckle', researchers examined the fine structure of different surfaces using a focused laser, and recorded the intensity of the reflection. The technique was tried on a variety of materials including matt-finish plastic cards, identity cards and coated paperboard packaging and resulted in clear recognition between the samples. This continued even after they were subjected to rough handling including submersion in water, scorching, scrubbing with an abrasive cleaning pad and being scribbled on with thick black marker.
(read the whole article here)

I see interesting potential here but first a few questions. A company produces a multi-ton roll of paper (or plastic), does the entire roll have the same DNA? If it changes inch by inch or front and back then a set area on a document needs to be scanned to obtain the same results each time. If the entire batch has the same DNA then security is needed to to protect the batch the same as the blank paper used to print currency.

Enough of problems with this process. How about some thoughts for the good.
Collectors will be able to certify items (paintings, historical letters, books). Of course if a counterfeit got certified it would then considered legitimate. Depending on the uniqueness of the DNA it may or may not be a cheap way to determine the age of an item.

When a credit card is issued the DNA of the plastic would be part of the account number. This would provide a two step authentication. 1) when the card is scanned by the merchant it verifies the DNA and 2) when the account is verified by the card company. This would require a change for the credit card company because the account number would change every time a new card was issued, but they already do this if you report a stolen card.

The same type approach could be taken for identity cards (driver's license, birth certificates, passports), that is print the numeric DNA of the paper on the document itself. This could immediately stop a casual forgery like underage drinkers making a fake id on the printer since the printed DNA would not match the actual DNA. Assuming the forger has access to a "DNA scanner" and prints the actual DNA of the forged document it would still be caught if checked against the official database.

I'm curious if the DNA falls within a certain range for the same type paper. For example if all the 60 pound paper of a particular color, fiber content, etc. have a DNA that falls within a certain numerical range. If so this gives the potential of rejecting a document because it is not "close enough" to the expected value. Possible uses:

• a retail merchant could verify if a sales receipt was issued by their store
  
• a corporate rep could quickly scan the packaging in store to see if it is counterfeit
  
• before a check is processed by your bank it can verify the check number to the paper DNA

And of course what happens to the demand for the ransom to be "unmarked bills"?

High alert code yellow little white lie
Pretty little girl is in disguise
Got a fake passport and a dossier
On a mission impossible every day
- from the song "Spy" by Bryan Paul Thomas (c) 2004