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Japan facing credit card number shortage

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Re: Japan facing credit card number shortage

#21

Post by amlib »

saas_sam wrote: post #3
gruez wrote: post #2

>the company decided to take makeshift measures such as reusing credit card numbers of discontinued cards after a certain period had passed since cardholders canceled their memberships. However, there are considerable risks of fraudulent usage What are the risks here, and why aren't they already present by someone generating credit card numbers with a RNG? AFAIK credit card transactions are authenticated by at least…

What if they switched CC numbers TO IPV6 addresses? Insane or genius?

Hopefully they keep the :: shortener in there....

Re: Japan facing credit card number shortage

#23

Post by sitharus »

rootusrootus wrote: post #17

I wonder how this became a problem. Your CC number is not just 16 digits long. It's 16, plus expiration, plus the 3-4 extra security digits, plus your name, plus your zip code. That's quite a lot of entropy.

That's not true. The number is just the number, though it can be more than 16 digits. The initial six digits identify the card issuer. Expiration and CVC/CCV are security checks, but only work in combination with the number. Name is generally not verified, though is often used in fraud assessment. Address verification is uncommon, and almost unused outside the US.

Re: Japan facing credit card number shortage

#24

Post by michannne »

jandrese wrote: post #16
michannne wrote: post #12

Earlier quoted context omitted.

I don't see how token based transactions would improve the situation. You still require a unique identifier per issuer per client per account.

The identifier is hidden from the user so if it's huge and complex that is no problem. My point is that we're talking about putting a lot of effort into overhauling the system to support a scheme that is arguably already obsolete. If we're putting in the effort we should just remove the old insecure digits entirely and focus on a cleaner modern solution.

The problem with that is the purpose of a credit card system is convenience, especially the convenience involved in being able to represent the identifier in an easily compact manner. When it's a few groups of digits, I can print it onto a card or piece of paper, and just plug the digits in whenever I need to validate the number and run a transaction. You can't do that with a token. What happens when I want to use my friend's computer to pay for something on Amazon but I haven't saved my card number? Or when I get a new card? I get that the current credit card system is monolithic and outdated, but it's purpose isn't to be modern, it's to be reliable, convenient, and adaptable, and it does a swell job at those things. There's absolutely no need to spend astronomical amounts of money to replace this system with something more modern.

Re: Japan facing credit card number shortage

#25

Post by Slartie »

saas_sam wrote: post #3
gruez wrote: post #2

>the company decided to take makeshift measures such as reusing credit card numbers of discontinued cards after a certain period had passed since cardholders canceled their memberships. However, there are considerable risks of fraudulent usage What are the risks here, and why aren't they already present by someone generating credit card numbers with a RNG? AFAIK credit card transactions are authenticated by at least…

What if they switched CC numbers TO IPV6 addresses? Insane or genius?

Only slightly more insane than keeping the handy 4x4 format, but extending it from base 10 numbers to base 16, which I would really love to see :D

Re: Japan facing credit card number shortage

#26

Post by samatman »

castratikron wrote: post #19
pcurve wrote: post #14

SUrely, there's some inefficiency in how numbers are used... 10 quadrillion for 7.5 billion people isn't enough?

"The first six digits represent the country, brand, and the type of card issuer and other elements". The last digit is a check digit so it's actually only 1 billion.

1 billion per country/brand/issuer tuple, that is.

It still seems like a comfortable amount of numbers.

Re: Japan facing credit card number shortage

#27

Post by wenc »

henearkr wrote: post #20
pcurve wrote: post #14

SUrely, there's some inefficiency in how numbers are used... 10 quadrillion for 7.5 billion people isn't enough?

The first digits are a header identifying the type of the card, (visa, mastercard...) and probably other characteristics. The main problem is that in Japan everybody has like 5 credit cards, because every big company has its own financial branch and issues cards (maybe to profit from a "reservoir" effect of the accounts?). So you have a credit card linked to your clothes shop, one from your supermarket, one from Raku…

> The main problem is that in Japan everybody has like 15 credit cards

This is a fascinating departure from my expectation, because when I was in Japan, I distinctly noticed that credit cards were not accepted everywhere. One could load money into Suica/Pasmo cards and use those at convenient stores, but I learned that carrying cash was imperative -- Japan seemed very much to be a cash-oriented society.

Re: Japan facing credit card number shortage

#28

Post by Swenrekcah »

Slartie wrote: post #25
saas_sam wrote: post #3

Earlier quoted context omitted.

What if they switched CC numbers TO IPV6 addresses? Insane or genius?

Only slightly more insane than keeping the handy 4x4 format, but extending it from base 10 numbers to base 16, which I would really love to see :D

This is genius. Make this happen fintech.

Re: Japan facing credit card number shortage

#29

Post by viraptor »

henearkr wrote: post #20
pcurve wrote: post #14

SUrely, there's some inefficiency in how numbers are used... 10 quadrillion for 7.5 billion people isn't enough?

The first digits are a header identifying the type of the card, (visa, mastercard...) and probably other characteristics. The main problem is that in Japan everybody has like 5 credit cards, because every big company has its own financial branch and issues cards (maybe to profit from a "reservoir" effect of the accounts?). So you have a credit card linked to your clothes shop, one from your supermarket, one from Raku…

"everyone" may be a bit extreme. There seems to be a national goal of going more cashless, but right now they're one of the most cash-based countries: https://www.statista.com/chart/19868/share-of-cash-payments-... Japan had 82% cash transactions compared to 14% in South Korea. From personal experience it's relatively normal to find a food place in Tokyo which has no card reader at all.

Re: Japan facing credit card number shortage

#30

Post by donor20 »

This is a ridiculous story.

Japan has a population of 150M.

If you can't give folks a number from SIXTEEN digits - something is wrong with the folks giving out the numbers.

Some answers to the excuses. The 6 digits at front, if a company legit runs out of numbers, ask for another prefix.

The reality. Instead of using the numbers properly (random ID to tie to a user account) they are probably putting some kind of structure into the digits that results in very inefficient use.

These are the 10 digits available PER PREFIX!

1,234,567,890

Even with a check digit you are at a billion numbers PER PREFIX! You can't get 125 million folks into this address space?

Absolutely pitiful.

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