NU013809@NDSUVM1.BITNET (Greg Wettstein) (07/26/89)
Here are a collection of replies that I received regarding the format and
recording density of the magnetic strips commonly found on bank cards
and credit cards.
Before I post the summary of replies I would like to pose an additional
question to the net. Based on what I have found I do not think that
the recording strip technology has sufficient density to meet our
storage requirements. A couple of the posters mentioned something which
they referred to as a 'smart card', I assume that these devices contain
something similar to an EEPROM which can be read and written to a number
of times. Our project group will probably be interested in pursuing
this technology.
I would be interested in conversing with anyone on the net who has
experience with 'smart card' or portable EEPROM technologies. I would
be interested in what types of data density are obtainable through these
devices and what type of external connections are needed to interface
with these devices, e.g. single pins, edge connectors, # of lines, power
requirements, read/write cycles etc.
Our project will probably require a customized device of some sort so
I would be interested in finding out if there are any companies that
do this type of work or would be capable of doing a custom devices such
as this. Once again replies either via e-mail or the net would be
gladly accepted. Once again thanks in advance.
As always,
G.W. Wettstein
NU013809@NDSUVM1
============================= Mag strip summary ======================
From: johnl@ima.ima.isc.com (John R. Levine) --------------------------
Glad you asked. The magnetic stripe format is standardized in ANSI X4.16, and
the format of the card itself is in ANSI X4.13.
According to X4.16, the stripe has three tracks. The first two are read-only,
the last is writable. Track 1 is recorded at 210 BPI in a six-bit ASCII subset.
The data can be up to 79 characters, and contains an account number, the full
name of the holder, the expiration date, a three digit country code, and a
parity byte. Track 2 is 75 BPI and contains the account number, expiration
date, and country code in BCD. Track 3 is the same format as track 1; its
contents are unspecified, at least in 1983 when the standard was written. The
content formats are conventional but don't appear to be mandatory, so any 79
bytes of six-bit text would be possible on tracks 1 or 3.
I have seen lots of mag stripe readers that plug into PCs, typically apppearing
either as a serial terminal or as "magic fingers" that type the stripe contents
on the keyboard. I've never seen a PC stripe recorder. I suspect that given
the fairly well founded paranoia of the credit card industry, stripe writers
would be relatively hard to get.
From: johnl@ima.ima.isc.com (John R. Levine) ------------------------
If you want to rewrite the contents of the card, you probably need a "smart
card" with an embedded chip as is used in payphone cards in France. I believe
that France Telecom is a leader in this technology; one could try calling their
office in New York and see if they sell it.
From: jimb@athertn.Atherton.COM (Jim Burke) ----------------------------
This is interesting. I happened to stop at a gas station near Clear Lake
California a few weeks ago and they used magnetic stripe technology to
operate their gas pumps. It worked like this: you go in and pay the
cashier any amount of money you want, up to a limit. The cashier passes
a thin plastic card (credit card sized but very thin) through what is
presumably a reader/recorder. You then take the card out to the pump
and pass it through a reader and pump your gas. I don't believe you
necessarily have to use all the credit on the card at one time - you
presumably could buy all your gas for the month at one time. When the
card is empty, you toss it into a little bin they provide. The pump
must write to the card in order to erase the credit. It seems like there
is room for abuse for this system if card reader/recorder devices were
readily available unless they used one heck-of-an encryption scheme on
the cards. Still, it is an interesting concept. Perhaps ten years from
now your employer will just hand you a little card instead of a paycheck
and you can carry it around with you to buy things, or swipe it through
your home unit (with a modem) to pay your bills. Handy, eh???
From: vail@tegra.UUCP (Johnathan Vail) --------------------------------
There is an ANSI spec that describes the encoding. Many companies
make encoders and readers. I think the readers we were using were
Sankyo Sieki (sp?). I had more info but I don't work for the
companies any more where I was doing this.
Segal's Law: A man with one watch knows what time it is. A man with two
watches is never sure.
From: george@rebel.UUCP (George M. Sipe) ------------------------------
The pump may just be reading a fixed ID from the card and passing that info
to a 'central' micro over in gas station HQ. Not much different than a bar
code.
From: dicky@sundts.uucp (Dick Wiersma) --------------------------------
I don't know if it would help you much, but lately I hear a lot about
"smartcards".
These are cards the size of creditcards, not with a magnetic strip but with
one or more chips on board.
They are not (yet) commonly used.
I know only one application at this time: "telephone credit card".
You buy a smartcard, and this gives you credit for a specific amount of
telephone ticks.
So I think the information is "editable", and secure!
Sorry I can't help you much further, good luck with your investigation
From: genemans@eleazar.Dartmouth.EDU (Jan Genemans) -------------------
I know of nothing specifically geared for the PC; however, engineering
calculators have been using magnetic card technology since the 70's. Both
Hewlett Packard and Texas Instruments have used such beasts. I'm not sure
as to Texas Instruments using the card readers anymore, but hp is still using
them. The HP41-C, CV, or CX use the same reader (~$150) plus the calculator
(~$80-$140), there is also a PC interface available for data exchange. Each
card can hold approx 50 lines of programming code or roughly 512 bytes on a
card side (.5" by 2.5"). This is all that I know. I haven't worked with the
PC interface so I cannot answer any questions.
From: bmarsh@cod.nosc.mil (William C. Marsh) ---------------------------
These cards are called ABA cards for American Banking Association. There is
an ANSI standard which probably deals with everything you want to know about
these cards and the encoding of them. The copy I have access to is pretty old,
(1974), so there may be a newer one out now.
ANSI X4.16-1973
American National Standards Institute
1430 Broadway
New York, NY. 10018
I work for a company which makes transaction processing systems for colleges,
and I have written code to decode this information. There are three 'tracks'
of data, we only look at track 2, where there are 40 nybbles of info there.
If you have some specific questions, I may be able to answer them, but I would
suggest getting a copy of this spec. Any good technical library should have it.
From: twb@cbnewsh.ATT.COM (thomas.w.beattie) ---------------------------
You should look into using SMART CARDS.
Like credit cards with a microchip for storing info.
From: lance@virgin.MV.COM (Lance Fraser) -------------------------------
I don't have any ideas about the strips, but I can give you
an alternative solution to your problem. I recently was involved
in the port of Lotus 123 to the NEC Ultralite and to another computer
that I can't mention yet. We ported Lotus to a 1 meg ROM card that is
about the size of a credit card (except 3 times as thick). The other
system has 1 ROM card for applications and 1 RAM card for data storage.
Both the NEC and the other system are IBM compatible computers that
can attach to your desktop and would offer you the interface you need,
The only problem with this system is that it is very expensive (I'm not
sure of the price, but I know it's more than the credit cards) but it
would work well if the information you need to store is valuable enough.
good luck,
From: Don Caprio <caprio@ttimv2.TTI.COM> -----------------------------
The bank cards can hold 3 tracks of data. Each tack can hold about 105
bytes of data. The ISO standard has track 3 at 105 bytes, track 2 at 38,
and track 1 at 77 bytes. This doesn't leave you much room. There is a
company that make a device you can hook up to a PC which will read and
write track data. I don't know the name of the company but if you need
to know send me mail and I'll walk over and take a look.
I've seen this credit card size device that has a bar code reader built
in. I guess they use it for inventory control. Once loaded up with data
you pop it into its reader and unload the data. Not sure if this will
work for you. I've seen it advertised in some of the PC mags like BYTE
or PC WORLD.
Good luck, hope this was some help.
From: Dave Taylor <dave%upvax.uucp@RELAY.CS.NET> -----------------------
Hp uses small magnetic card strips to feed 41c** series calculators
and probubly have a pc interface for either the cards or the calculator.trgauchat@rose.waterloo.edu (Terry Gauchat) (07/27/89)
In article <2587NU013809@NDSUVM1> NU013809@NDSUVM1.BITNET (Greg Wettstein) writes: }Here are a collection of replies that I received regarding the format and }recording density of the magnetic strips commonly found on bank cards }and credit cards. }From: jimb@athertn.Atherton.COM (Jim Burke) ---------------------------- }This is interesting. I happened to stop at a gas station near Clear Lake }California a few weeks ago and they used magnetic stripe technology to }operate their gas pumps. }The pump }must write to the card in order to erase the credit. It seems like there }is room for abuse for this system if card reader/recorder devices were }readily available unless they used one heck-of-an encryption scheme on }the cards. } } }From: george@rebel.UUCP (George M. Sipe) ------------------------------ }The pump may just be reading a fixed ID from the card and passing that info }to a 'central' micro over in gas station HQ. Not much different than a bar }code. } Our school library (and others) uses these type of cards ("Vendacards") for photocopiers. You prepay to get $5.00 credit, and the copier removes 5 cents for each copy. Copiers are spread over campus, so a central computer is unlikely. Also, the Vendacard for this school doesn't work at the other (though they look the same...). ...Terry.