Path: utzoo!utgpu!watserv1!watmath!iuvax!mailrus!accuvax.nwu.edu!nucsrl!telecom-request
From: psrc@pegasus.att.com (Paul S. R. Chisholm)
Newsgroups: comp.dcom.telecom
Subject: Re: Phone Credit Cards
Message-ID: <3584@accuvax.nwu.edu>
Date: 7 Feb 90 04:22:19 GMT
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X-Telecom-Digest: Volume 10, Issue 80, message 3 of 10


Sorry, this is straying a little off topic.

In article <3532@accuvax.nwu.edu>, dave%westmark@uunet.uu.net (Dave Levenson) 
writes:

> Note: Bank ATM cards, like telco cards, _do_ have your PIN
> magnetically encoded on the card.  It is nice of the banks, however,
> to have thought of not printing it in a human-readable place on the
> card.

The PIN (personal identification number; the "password", so to speak,
as compared with the personal account number or PAN, the "login ID")
is *NOT* stored on ATM or debit cards, not even in encrypted form.  I
think a checksum *is* stored, to allow for some off-network
validation.

One of the problems banks have with PINs is that people can't remember
them . . . so they write them on the card!  Great security, huh?

My favorite story about PINs involves Al Brown, a plastic card pioneer
who recently retired from AT&T.  He went to Japan, where they showed
him a plastic card, and proudly told him that the PIN was stored on
the card.  Al pulled a loop reader out of his pocket, a little gizmo
with a sheet of magnetic bubbles (or some such) that make magnetic
fields visible.  He ran it over the card, passed the card back, and
told his hosts what the PIN was!  The engineers conferred in a side
office, returned after a few minutes, and announced their solution:
"Don't give cards to tricky Americans!"


Paul S. R. Chisholm, AT&T Bell Laboratories
att!pegasus!psrc, psrc@pegasus.att.com, AT&T Mail !psrchisholm
I've never been involved with AT&T Calling cards, and I'm *definitely*
not speaking for the company, I'm just speaking my mind.