On December 1, 2008 at 14:27 johnl(_at_)taugh(_dot_)com (John Levine) wrote:
} coffee. But 98% of the cash that customers offer is counterfeit. How
} would this affect the way that cashiers work? Would they just accept
} all the cash and figure they'll call the cops when they find bogus
} stuff?
I suspect they'd make everyone pay in advance so they have time to
confirm the cash is real, and then only provide service to those who
have an account in good standing. Then it may turn into a problem
with identity theft, but that doesn't hit their bottom line.
Then 98% pay with fake versions of whatever it is that they give you
to say that you have an account. Same problem. This isn't a perfect
analogy, since at a donut store you rarely have 1000 people
simultaneously at 1000 counters trying to buy a donut with the same
card that has only 50 cents on it.
I will say that, having worked and grown up in retail, people who pass
phony bills try to find very busy cashiers to pass them thru.
A big problem at Coney Island food stands and similar, which can get
impossibly busy, were people who'd cut the corners off a $20 bill and
paste them onto a $1 bill. The $20 is still good (hand it in at the
bank, rule is usually >50% then ok), and the $1 gets accepted by the
busy cashier as a $20. And no print counterfeiting involved! Any idiot
with scissors and glue can try it tho I think it's as serious a crime
as any counterfeiting, or more serious than most people would call fun
anyhow.
And on and on. All kinds of con games, slight of hand, I could teach
you a few which really work but even better with a busy cashier.
But cryptography gives us a potentially 100% (ok, 99. with a lot of
9s%) certain identification of phony "bills", much like even an
average bill scanning machine would never be fooled by those clipped
corners, and a pretty good one can spot most any phony.
} ... if your wonderful system rejects their fake stamps with 99%
} accuracy, they try 100 times as often ...
.... Let through unchecked anyone with a history of payment and
throttle everyone else (to the point of quarantine without final
delivery, if necessary) until you know their history.
That's what Turntide does, except for "history of wanted mail."
Why would "history of paying" be better?
I wouldn't use any "history of paying".
I would expect "history of fraud" to be of interest, particularly if
positive ID were required a la DKIM or similar.
--
-Barry Shein
The World | bzs(_at_)TheWorld(_dot_)com |
http://www.TheWorld.com
Purveyors to the Trade | Voice: 800-THE-WRLD | Login: Nationwide
Software Tool & Die | Public Access Internet | SINCE 1989 *oo*
_______________________________________________
Asrg mailing list
Asrg(_at_)irtf(_dot_)org
https://www.irtf.org/mailman/listinfo/asrg