Gasboy CFN III Mgnr's Mnl V3.4 - Manual (Page 302)

Appendix F: Dialout Communications Credit Card Numbering
Page F-2 MDE-4315 CFN Series CFN III Manager’s Manual for Windows NT · August 2004
Credit Card Numbering
Credit cards are identified by the account number prefix (the first digit or digits) and the
number of digits in the account number. For example, VISA credit card account numbers all
start with 4, and they have either 13 or 16 digits.
However, electronic card readers cannot always distinguish a card’s type (for example, credit
card, phone card, library card, or video rental card) just by that card’s magnetically encoded
number. And some of these other special purpose cards, which you certainly do not want to
accept for payment, may even have the same encoded numbers as valid credit cards.
Confusion can even occur between different types of credit cards, such as Carte Blanche and
Diner’s Club.
Consult your bank or card network for current information about the account number prefix
and length.
Handling Transactions
Accepting debit or credit cards in transactions usually consists of three parts: authorization
(called verification by Gasboy), data capture, and settlement.
Authorization (verification)
No verification This method is not recommended, due to the financial risk
involved.) No checking - except for the mod 10 check digit, and
then only if so configured - is done on the status of the card.
Local lockout (This method is not recommended, due to the financial risk
involved.)
Credit and debit cards are verified in the same ways as
privately issued cards, through the CFN III’s lockout options
(which are described in the Card Lockout chapter of the
System Administrator’s Manual for version 1.0 and in the
Proprietary Cards section of this manual). Do not use local
authorization for debit card transactions, since the bank that
issued the card must be contacted to check the PIN that the
customer entered.
Only limited lockout is appropriate for local authorization of credit
cards. (Bit-mapping is used only for private-issue cards; you
cannot have both limited and bit-mapped lockout.)
You must set up the local lockout file to include information
about the ranges of card numbers you want to accept. You can
also specify certain card numbers as valid or invalid.