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Path: utzoo!utgpu!water!watmath!sunybcs!colonel
From: colonel@sunybcs.UUCP
Newsgroups: sci.crypt
Subject: Re: bank card
Message-ID: <3422@sunybcs.UUCP>
Date: Fri, 15-May-87 13:50:00 EDT
Article-I.D.: sunybcs.3422
Posted: Fri May 15 13:50:00 1987
Date-Received: Sat, 16-May-87 15:44:49 EDT
References: <599@umnd-cs.D.UMN.EDU> <5747@eddie.MIT.EDU> <27595@rochester.ARPA>
Organization: Jack of Clubs Precision Instruments
Lines: 27

>                ... He put in a non-participating bank's card and the
> machine cycled him through the whole validation sequence before
> spitting out the card with the message "invalid card" or something like
> that. So it looks like the ATM makes up a whole package of info before
> firing it off to the mainframe. I can just imagine the Cobol code, yuk!

It's a standard security practice--good policy.  Under other conditions,
though, it can be silly.  Example from my wife:

	1. Insert card.
	2. Type i.d. number, with an error.
	3. Select transaction.
	4. Transaction fails--wrong i.d. number.
	5. Go to 3 (!).

I won't embarrass her by telling how long it took her to get out of
the loop, but you get the idea.

==
	"We Spies, or Us Spies - for we call ourselves both - ..."

				--S. Leacock
-- 
Col. G. L. Sicherman
UU: ...{rocksvax|decvax}!sunybcs!colonel
CS: colonel@buffalo-cs
BI: colonel@sunybcs, csdsiche@ubvms