DAEDALUS
David Jones
For years now, we have been told that the cashless society is
just around the corner. Every shop will have a computer terminal;
simply enter the transaction, validate it with your personal card, and
the central computer will transfer the sum specified from your bank
account to that of the shop. Wonderful! The reason why it doesn't
happen is that fraud would be so easy. Card fraud is so widespread
already that the banks daren't risk anything worse. But Daedalus has
the answer. His new cash-card is unstealable: the user's own
thumbnail.
A nail has a smooth and uniform surface, and is transparent
enough to let through the light from a laser. A small laser could
bring a brief light pulse to a focus in the body of the nail, burning
a tiny white mark that could easily be read, but would be protected
from chance abrasion. A dot-matrix pattern of such marks could easily
encode a financial transaction. A nail has no nerves so the process
would be quite painless. Accordingly, the new Dreadco financial
terminal has, besides a keyboard for entering the transaction, a
thumb-port to admit the user's thumb.
Every day a nail grows about a tenth of a millimetre. With laser
dots about the size of those on a compact disc , this would give space
for about ten new transactions. Over time the user will accumulate on
his thumbnail a running financial statement showing all his
transactions for the past few months. Each time he inserts his thumb
into a terminal, the sytem will check that statement against its file.
If everything matches, his identification is secure; the terminal
accepts the new transaction and prints it below the previous ones.
But if there is a discrepancy, it sounds an alarm and clamps down on
the suspect thumb, trapping the fraudster until the police arrive!
But suppose a bent manicurist manages to photograph a client's
thumbnail, and uses it to construct a forged thumb? Even then, the
fraud is risky. By the time the forged thumb is ready, the victim
will probably have used the system again. The forgery will not carry
this latest transaction: it will be detected and trapped by the
terminal, for the police to study later as evidence.
Daedalus' new thumbcard will impose financial prudence on its
users. The spendthrift who fills his thumb up with wild transactions
will soon be choked off by sheer lack of space. On the other hand,
should he go down with mumps or measles (which arrests nail growth)
bankruptcy would rapidly threaten. And secrecy is not really assured.
Gigolos with magnifiers may shrewdly revive the old gallantry of
hand-kissing: gypsy palmists will read both sides with great care;
shady financial operators of both sexes may take to wearing opaque
nail varnish. And a death in the family will have the sorrowing
relatives hastily erasing the deceased's thumbs with a
laser-scrambler, before some unscrupuous undertaker or body-snatcher
can detach or copy them to filch their encoded legacy.
The Guardian
24 May l988
