Value of an old IBM PS2 CL57 SX Laptop 3334

re:

so we annalysed this when we started work on x9.59 in the mid-90s ... and in the x9.59 financial standard, changed the paradigm.

a crook with just the knowledge of an account number (used in x9.59 transactions) can no longer perform a fraudulent transaction.

the role of account number as some sort of authentication shared-secret is eliminated,

overloading of the account number is eliminated and account number is then used purely for business process operations. the millions of places that account numbers are needed and readily available, no longer represent sensitive operations that are also responsible for never divulging the account number.

this is also the point of my old security proportional to risk posting

... the business value of an account number (in all these processes) may reprensent only a few dollars to a merchant ... but to the crook (either insider or outsider) represents potential value equivalent to the account credit limit. no only is their the impossibility of simultaneously making the account number generally available for the myriad of business process and at the same time keeping the account number confidential and never divulging it ... but there is a significant mismatch between the value of the account number to the "defenders" and the value of the account number to the "attackers" (and, in fact, studies find something like 70 percent of idenbreasty and account theft incidents involve insiders).

for a little drift, the transaction card cost for some merchants, can even be larger than the profit from the transaction, i.e. the value that the transaction represents to the merchant:

posted in the above:

from above

Fed up with out-of-control interchange fees, retailers are fighting back with concerted legal and educational tactics -- and, in some cases, proactive offensives of their own.

...

from above:

Convenience store operators can make more money on a 12-ounce cup of coffee than they can on a 12-gallon tank of gas. Credit card fees now account for almost half of a typical store's expenses - more than labor.

... snip ..

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