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Old March 2nd 12, 03:25 AM posted to uk.railway,uk.transport.london,misc.transport.rail.americas
Stephen Sprunk Stephen Sprunk is offline
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First recorded activity at LondonBanter: Aug 2004
Posts: 172
Default cards, was E-ZPass, was CharlieCards v.v. Oyster (and Octopus?)

On 01-Mar-12 19:56, Adam H. Kerman wrote:
Charles Ellson wrote:
On Thu, 01 Mar 2012 19:05:59 -0600, Stephen Sprunk wrote:
On 01-Mar-12 17:51, Adam H. Kerman wrote:
Stephen Sprunk wrote:
There is no way for the terminal to know whether the Visa/MC/etc. number
presented is a credit, debit or charge card. A card processor _may_ be
able to deduce it from other information, but only the issuing bank
knows for sure.

I have no idea how you come up with this stuff, but the type of card,
not to mention who issued it, is built into the number range itself.

The first digit or two identifies the network; the next several digits
identify the issuing bank. Nowhere in the number is encoded whether it
is a credit, debit or charge card. Even if some issuing banks choose to
encode that in the remaining digits, there is no guarantee they will all
do so--or in the same way.


http://bin-iin.com/visa-BIN-range.html
for some VISA listings.


Oh, look: 4416 69 Visa Gift Card

Any number of the ranges are for debit cards. I assume ranges not
listed are for Master and other card brands. ATM cards would be
in their own ranges, separate from other debit cards.

All this stuff is known. The whole list is for sale for under $200
on that Web page.


My primary bank issues both debit and credit cards using the same BIN.
Even for issuing banks with multiple BINs, it's not like there is a
fixed digit in the number that will tell you; you would need to download
and store the entire database (and keep it updated) to be able to deduce
whether a given card number was debit or credit. I'm not aware of any
_terminal_ that does that. They simply doesn't need to know; they
submit the authorization to the card processor (which presumably _does_
maintain that database), and the card processor lets the terminal know
if it needs to collect a PIN, EMV signature, etc. to proceed. Or
perhaps the card processors don't need to know either and such
instructions, if applicable, come from the issuing bank.

S

--
Stephen Sprunk "God does not play dice." --Albert Einstein
CCIE #3723 "God is an inveterate gambler, and He throws the
K5SSS dice at every possible opportunity." --Stephen Hawking