unforgeable optical tokens?

[James A. Donald]

    --
Perry E. Metzger wrote:
> > http://www.nature.com/nsu/020916/020916-15.html
> >
> > An idea from some folks at MIT apparently where a physical
> > token consisting of a bunch of spheres embedded in epoxy is
> > used as an access device by shining a laser through it.

On 21 Sep 2002 at 0:04, David Wagner wrote:
> Yeah.  I think it's neat!
>
> This is not a replacement for cryptography.  It's not
> biometric authentication.  It's no good for
> challenge-response authentication across a network.  It's not
> a secure credit card.
>
> What is it, then?  It's a physical object that's hard to
> duplicate. I'd describe their work by analogy to marbles.
> Marbles are more-or-less unique.

Each piece of wood or parchment is also similarly unique.  The
knights templar used this for cheques.  The parchments in your
checkbook would have another half kept in the the temple, so
when a cheque was presented to the temple for payment, they
would compare the bits of parchment for a match.

The uniqueness of wood was, and probably still is, used for
signatures in Hong Kong.   You would mark the paper with a
wooden stamp, using a fingerprint like inking that showed the
grain of the wood.   This created a mark that was difficult to
duplicate.

Unfortunately, I do not yet see any applications for these
tokens that are as useful as the chequebooks of the knights
templar, or the stamps of Hong Kong, though perhaps some sharp
person will soon invent one. 

    --digsig
         James A. Donald
     6YeGpsZR+nOTh/cGwvITnSR3TdzclVpR0+pr3YYQdkG
     1zOSLvsmHrZmIaMMOQWUokjt+1GnFCdu2KnEXTYf
     4+Z4n1kFr3OElCX6pFomVfIwLoJinCHtNtns9yqjD


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