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Author Topic: Bitcoin Credit Card Design  (Read 5092 times)
dark_st3alth (OP)
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December 09, 2011, 05:03:16 AM
Last edit: December 10, 2011, 11:57:53 PM by dark_st3alth
 #1

Just something I did when I was board.

A sort of credit card design I made. Includes a SHA512 hash and a MD5 hash which I know.

Not done, but I'll work on it. If you feel like donating, please see my signature. Thanks!

http://i.creativecommons.org/l/by-nc-nd/3.0/88x31.png
Bitcoin Magnetic Card Designs by DarK_St3alth is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.

Fronts:
http://img341.imageshack.us/img341/3673/frontj.th.png http://img687.imageshack.us/img687/8274/front2d.th.png http://img3.imageshack.us/img3/7326/front3.th.png http://img542.imageshack.us/img542/7326/front3.th.png http://img194.imageshack.us/img194/9596/front5.th.png

Backs (if you can print them):
http://img217.imageshack.us/img217/2120/backap.th.png



All images uploaded with ImageShack.us

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December 09, 2011, 05:08:01 AM
 #2

Just something I did when I was board.

A sort of credit card design I made. Includes a SHA512 hash and a MD5 hash which I know.

Not done, but I'll work on it. If you feel like donating, please see my signature. Thanks!


Bitcoin Credit Card Design by DarK_St3alth is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.





Frickin' nice! Very nice! Personally, I'm having trouble getting my head wrapped around the term 'Credit Card'. Perhaps a different word or term for what you have here is in order. Hopefully the community can help me (us) out with this issue I'm having.

Thoughts?
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December 09, 2011, 05:09:50 AM
 #3

This guy accepts designs, and gives a portion of the profit to the designer. Submit the designs, and I will buy some. https://bitcointalk.org/index.php?topic=46933.0

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December 09, 2011, 08:11:18 PM
 #4

Frickin' nice! Very nice! Personally, I'm having trouble getting my head wrapped around the term 'Credit Card' . Perhaps a different word or term for what you have here is in order. Hopefully the community can help me (us) out with this issue I'm having.


I think the more appropriate term would be debit card..  Just instead of the funds coming out of your bank account, they'd come out of your wallet. 

The only issue is.. since there is nothing on the card to allow you to "push" the funds by initiating a payment, a protocol would have to be developed for a "pull" transaction ...  This does, of course, involve a level of trust in where you "swipe" your card since you would really have no control over the amount of the "pull" and no recourse if more-than-expected funds were taken from your wallet.

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December 09, 2011, 08:33:45 PM
Last edit: December 09, 2011, 09:01:20 PM by cbeast
 #5

We have become so accustomed to credit cards, it's hard to imagine life without them. A major problem with magnetic strips is that they are easily erased. Instead of a magnetic strip, why not just use cards loaded with small QR private key paper coins embedded. They can be removed and replaced after they are used. Change can be made to the public key. Backups can be kept stored with online wallet services in case the card is lost, and the Bitcoin balances on them can be moved to new addresses. This would be like a combination check/card. ATMs and cash registers can be adapted to even print new private keys to reload the check/card and send a backup to the online wallet.

[edit] Actually, I don't like the idea of paper either. Some sort of non-magnetic mechanical device to form QR codes would be better.
[edit 2] Memory metal would work for this. The code can be stamped and erased with heat.

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December 09, 2011, 09:32:02 PM
 #6

Frickin' nice! Very nice! Personally, I'm having trouble getting my head wrapped around the term 'Credit Card'. Perhaps a different word or term for what you have here is in order. Hopefully the community can help me (us) out with this issue I'm having.

I've been referring to these as "Pay Me" cards, since they basically perform the exact opposite duty of a credit card.  (Probably not the best term, but I sort of copied that from a sci-fi TV show I was watching that referred to ID as a Show Me card.)

Instead of being used to give money, you use them to receive a payment.  Hand your card to someone, he scans it with a mobile device, and then transfers coins to your account.  You could do the same with a cell phone generated QR code, but a card eliminates the need to hand a potential stranger your valuable and rather personal mobile device.

The concept of pulling funds from an account, as is done with basically all modern banking and credit cards, is one of the most fundamental ways the entire banking system is flawed.  It will take a little change in thinking to get used to this reversal in how funds are transferred, but we'll all be much better off in the end.

By the way, I can have your card printed for you at www.paymyaddress.com.  I do also offer a 20% commission on sales from contributed designs.  So far, the best sellers have been my original design and design #5 (the one with the Casascius coin background).

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December 09, 2011, 11:59:39 PM
 #7

Frickin' nice! Very nice! Personally, I'm having trouble getting my head wrapped around the term 'Credit Card'. Perhaps a different word or term for what you have here is in order. Hopefully the community can help me (us) out with this issue I'm having.

I've been referring to these as "Pay Me" cards, since they basically perform the exact opposite duty of a credit card.  (Probably not the best term, but I sort of copied that from a sci-fi TV show I was watching that referred to ID as a Show Me card.)

Instead of being used to give money, you use them to receive a payment.  Hand your card to someone, he scans it with a mobile device, and then transfers coins to your account.  You could do the same with a cell phone generated QR code, but a card eliminates the need to hand a potential stranger your valuable and rather personal mobile device.

The concept of pulling funds from an account, as is done with basically all modern banking and credit cards, is one of the most fundamental ways the entire banking system is flawed.  It will take a little change in thinking to get used to this reversal in how funds are transferred, but we'll all be much better off in the end.

By the way, I can have your card printed for you at www.paymyaddress.com.  I do also offer a 20% commission on sales from contributed designs.  So far, the best sellers have been my original design and design #5 (the one with the Casascius coin background).



Sure I'd be happy to submit some designs. Is there something different I should change or add?

I'd like to get with that whole "credit" or "debit" card idea, but it seems like a costly investment. I thought of adding a barcode for POS systems, but I'll see what you think.
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December 10, 2011, 12:42:42 AM
 #8

What does the card do?  How does it work?  Can you give us a simple use case?  Is it a "Pay Me" card that just has my public information on it so others can pay me or are you trying to figure out a way to use it to pay others and buy things with it (like the current fiat money denominated credit and debit cards)?

What is your vision here?

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December 10, 2011, 04:05:59 AM
 #9

A major problem with magnetic strips is that they are easily erased.
Partially wrong. HiCo magnetic strips are really sturdy. I tried to erase credit card from year 1998 with HiCo magstripe on it. I rubbed it against permanent magnet pulled from old radio loudspeaker. The same magnet is able to damage audio tape and sometimes it can damage standard High Density floppy discs. The credit card worked without any errors in my MSR-206 reader.

P.S. Magstripe readers are much cheaper and simpler devices than optical recognition systems needed for QR codes.

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December 10, 2011, 04:10:25 AM
 #10

Here is an old thread that may be of interest:  https://bitcointalk.org/index.php?topic=46366.0

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December 10, 2011, 05:15:22 PM
 #11

What does the card do?  How does it work?  Can you give us a simple use case?  Is it a "Pay Me" card that just has my public information on it so others can pay me or are you trying to figure out a way to use it to pay others and buy things with it (like the current fiat money denominated credit and debit cards)?

What is your vision here?

I think people have found valid solutions to pay with bitcoins, but not a perfected.

QR codes have finally got more popular up here in Canada, but there are a few flaws with them.

- The camera needs to be decent, which tends to be on smartphones
- A "app" needs to be developed to pay with bitcoins which can be a little security hazard
- The QR code has to be big enough but small enough so it's easy to scan
- The "app" needs to made well to read the QR codes, I've used a few on Windows Mobile, one was great and the rest failed to even the code in the same environment.
- QR codes seem to be a "work around" solution if you get what I mean.


My vision is that you would be able to go to any store and this happens:

Cashier: "How do you want to pay for this?"
You: "Bitcoins please"
Cashier: "Sure, just swipe your card."

Being able to do it would make BTC very popular, it would have some of the lowest fees in history, and almost everyone would be able to take them. The setup costs, and usage costs would also be much lower.

The only real problem is the initial investment for the cards. I mean the real ones, signature panel, stamped numbers and magnetic strip. Costs about $200+ USD for about 50 I think.

Someone may come along and say "OMG! HE'S GOING TO MESS THE WHOLE MARKET UP!" - This is not my point.

Someone will have to do the payments, and I want to stay away from those dirty banks Wink. A simple program that I could design and make would perform all the tasks to transfer bitcoins for almost no fee (and side note, I'm working on a pay/transfer via url thing as well, eg. btc:\\pay\myaddress).


This is where I'd like to see bitcoins go, because right now they are only practical for internet usage, and a one off smartphone transfer via QR code. Magnetic swipe cards would be fast and easy. We could even go to RFID tags, but it's another attack surface I think it would be fairly reasonable to avoid.
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December 10, 2011, 05:24:45 PM
 #12

In among the usual personal crap there is a LOT of good information and ideas in this thread.  It describes using standard cards and other solutions using more advanced cards, etc.  I think if you go throught the whole thing and ignore the personal stuff there are some good ideas in there:  https://bitcointalk.org/index.php?topic=46366.0

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December 10, 2011, 05:46:43 PM
 #13

A major problem with magnetic strips is that they are easily erased.
Partially wrong. HiCo magnetic strips are really sturdy. I tried to erase credit card from year 1998 with HiCo magstripe on it. I rubbed it against permanent magnet pulled from old radio loudspeaker. The same magnet is able to damage audio tape and sometimes it can damage standard High Density floppy discs. The credit card worked without any errors in my MSR-206 reader.

P.S. Magstripe readers are much cheaper and simpler devices than optical recognition systems needed for QR codes.

Good to know. OK then. Casascius and others will have a working POS soon that we can use with a real Bitcoin debit card. I was under the impression that QR codes were the new thing. I guess they are best used for writing secure checks.

Any significantly advanced cryptocurrency is indistinguishable from Ponzi Tulips.
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December 10, 2011, 05:55:23 PM
 #14

There is no need for stamped letters. The stamped letters on credit cards are legacy from earlier days of credit cards. Today most debit cards in europe (Visa Electron and Maestro) have only imprinted numbers.

There is no need for extra items on Bitcoin cards, only the magstripe is needed. They can be very cheap in bulk. In opposite to credit cards, Bitcoin cards have no need to be protected by card design and hidden UV texts and similar. You can forge a fake credit card, but You can't make a fake Bitcoin.

And how much info needs to be stored on the cards? Will they fit into ISO specified tracks?

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December 10, 2011, 06:16:47 PM
 #15

There is no need for stamped letters. The stamped letters on credit cards are legacy from earlier days of credit cards. Today most debit cards in europe (Visa Electron and Maestro) have only imprinted numbers.

There is no need for extra items on Bitcoin cards, only the magstripe is needed. They can be very cheap in bulk. In opposite to credit cards, Bitcoin cards have no need to be protected by card design and hidden UV texts and similar. You can forge a fake credit card, but You can't make a fake Bitcoin.

And how much info needs to be stored on the cards? Will they fit into ISO specified tracks?

I wouldn't think it would be too much. I've forgotten the format since last week when I looked at it, but Wikipedia always helps Smiley.

I looked and it seemed that the ISO/IEC 7813 standard would work:

Code:
Track 1

The Track 1 structure is specified as:

    STX : Start sentinel "%"
    FC : Format code "B" (The format described here. Format "A" is reserved for proprietary use.)
    PAN : Primary Account Number, up to 19 digits
    FS : Separator "^"
    NM : Name, 2 to 26 characters (including separators, where appropriate, between surname, first name etc.)
    FS : Separator "^"
    ED : Expiration data, 4 digits or "^"
    SC : Service code, 3 digits or "^"
    DD : Discretionary data, balance of characters
    ETX : End sentinel "?"
    LRC : Longitudinal redundancy check, calculated according to ISO/IEC 7811-2

The maximum record length is 79 alphanumeric characters.
Track 2

The Track 2 structure is specified as:

    STX : Start sentinel ";"
    PAN : Primary Account Number, up to 19 digits, as defined in ISO/IEC 7812-1
    FS : Separator "="
    ED : Expiration date, YYMM or "=" if not present
    SC : Service code, 3 digits or "=" if not present
    DD : Discretionary data, balance of available digits
    ETX : End sentinel "?"
    LRC : Longitudinal redundancy check, calculated according to ISO/IEC 7811-2

The maximum record length is 40 numeric digits.

Of course it would need to be changed, so here's what I thought:

Code:
Track 1

The Track 1 structure is specified as:

    STX : Start sentinel "%"
    FC : Format code "B" (The format described here. Format "A" is reserved for proprietary use.)
    PAN : 0000000000000000000 (Translation account number, where the service would convert this to the actual place to take from)
    FS : Separator "^"
    NM : DarK Stealth (The card holder for ID checks)
    FS : Separator "^"
    ED : ^ (None, this card should last a life time)
    SC : ^ (No service code)
    DD : Discretionary data, balance of characters
    ETX : End sentinel "?"
    LRC : Longitudinal redundancy check, calculated according to ISO/IEC 7811-2

The maximum record length is 79 alphanumeric characters.
Track 2

The Track 2 structure is specified as:

    STX : Start sentinel ";"
    PAN : 0000000000000000000 (Translation account number, where the service would convert this to the actual place to take from)
    FS : Separator "="
    ED : = (None, this card should last a life time)
    SC : = (None, this card should last a life time)
    DD : Discretionary data, balance of available digits
    ETX : End sentinel "?"
    LRC : Longitudinal redundancy check, calculated according to ISO/IEC 7811-2

The maximum record length is 40 numeric digits.

Thinking about it, we could really just have a magnetic stripe, as it would be cheaper.
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December 23, 2011, 09:30:18 AM
 #16

Could we make a card with the public key visible and the private key only visible under UV or some other obscuring scheme? I'm thinking a card like this could be "charged up" via the public key and then the private key could be swept in a more secure environment to make purchases.

Any significantly advanced cryptocurrency is indistinguishable from Ponzi Tulips.
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December 23, 2011, 03:07:15 PM
 #17

I need to know what data MUST be on the magstripe tracks. The ISO format for contents probably is not needed as it may not fit the data. It's designed for bank accounts.

Track1: Private key to sign transactions. Some checksum digit at the end
Track2: receiving address. The starting character can be 1
Track3: Other??? No need for name of cardholder or date of expiry. The bitcoin must be anonymous and the coins will not expire. When card wears out, it can be copied to new one.

When exact needed data will known, I will try to write that on standard loco card.

The drawback is that coins can be spent with single private key must be recieved to the same address. I'm right? This means the bitcoin receiving address can be linked to single cardholder.

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December 23, 2011, 10:19:52 PM
 #18


I've been referring to these as "Pay Me" cards, since they basically perform the exact opposite duty of a credit card.  (Probably not the best term, but I sort of copied that from a sci-fi TV show I was watching that referred to ID as a Show Me card.)

Instead of being used to give money, you use them to receive a payment.  Hand your card to someone, he scans it with a mobile device, and then transfers coins to your account.  You could do the same with a cell phone generated QR code, but a card eliminates the need to hand a potential stranger your valuable and rather personal mobile device.

The concept of pulling funds from an account, as is done with basically all modern banking and credit cards, is one of the most fundamental ways the entire banking system is flawed.  It will take a little change in thinking to get used to this reversal in how funds are transferred, but we'll all be much better off in the end.

By the way, I can have your card printed for you at www.paymyaddress.com.  I do also offer a 20% commission on sales from contributed designs.  So far, the best sellers have been my original design and design #5 (the one with the Casascius coin background).


Interesting!  Perhaps relevant is that this is the way checks work in Europe.  A check is not  something you take to the bank to deposit, it is something you take to the bank to pay.  My utilities send me a check every month. 
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January 16, 2012, 09:32:07 AM
 #19

I've been referring to these as "Pay Me" cards, since they basically perform the exact opposite duty of a credit card.

...

Instead of being used to give money, you use them to receive a payment.  Hand your card to someone, he scans it with a mobile device, and then transfers coins to your account.

So you'd want a Pay Me QR code posted by the merchant.  Scan it with your device, your app feeds BitCoin an address and, ideally, a total cost.  It then sends the BTC automatically once you've confirmed the transaction, and once the merchant has gotten sufficient verification from the network the transaction is successfully completed.

More optimally, merchants would generate a unique per-transaction QR code.  This would enable correct pricing and easy verification of which transaction it was that had just processed.  Per-transaction QRs could be generated on receipt paper (pre-ceipts?  QR billing?) or perhaps even just generated on a screen to be scanned with the customer's mobile device.

So what you'd seem to actually want is an app.  Easier and more cost-effective than physical materials anyway.


Be well,

- Satori
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January 16, 2012, 02:44:31 PM
 #20

I need to know what data MUST be on the magstripe tracks. The ISO format for contents probably is not needed as it may not fit the data. It's designed for bank accounts.

Track1: Private key to sign transactions. Some checksum digit at the end
Track2: receiving address. The starting character can be 1
Track3: Other??? No need for name of cardholder or date of expiry. The bitcoin must be anonymous and the coins will not expire. When card wears out, it can be copied to new one.

When exact needed data will known, I will try to write that on standard loco card.

The drawback is that coins can be spent with single private key must be recieved to the same address. I'm right? This means the bitcoin receiving address can be linked to single cardholder.
Having a private key would make it easy to steal. I wonder if part of a private key could be had, and the user would have to enter another part of it kind of like a PIN.

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