On 01-Mar-12 08:40, Adam H. Kerman wrote:
Neil Williams wrote:

I've seen them used on trains (in the buffet car mainly), but more
common is an integrated ticket and payment machine. Traditionally
the railway did not pre-authorise at all (at their risk) but with
on-train Wi-Fi and mobile phone based devices this is likely to
change.

That's very interesting. However, couldn't these devices be loaded with
lists of invalid and canceled credit card numbers?

Before the advent of telephone authorization, credit card companies
would send merchants small books each month listing all of the invalid
and/or canceled cards that had not yet expired. However, even by the
1980s, this proved impractical--and the number of cards circulating
today is at least two or three orders of magnitude greater.

Also note that many consumers today have _valid_ cards with little/no
available credit, so it's not sufficient anyway if a merchant wants to
ensure their transaction will be accepted.

S

--
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