Live data from Hacker News

Japan facing credit card number shortage

mainichi.jp

71–80 of 360 posts

Re: Japan facing credit card number shortage

#71
post #3

Earlier quoted context omitted.

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

Why stop there? ipv6 license plates, citizen numbers, home addresses, part numbers, atoms, ...

You joke, but that’s exactly what uuid/guid is — 128 bit identifiers. The only difference is that ipv6 is allocated hierarchically.

Re: Japan facing credit card number shortage

#72

Earlier quoted context omitted.

Ok... sounds like it would take longer at online checkout then.

Unless somebody wrote an app, or the store cooperated like PayPal, or 100 other things. Lets try to imagine a better future?

Don't you already get this with Verified by Visa and MasterCard SecureCode? You don't need new credit card numbers to do this.

But merchants don't implement it... because it's an extra step and consumers don't like it. The very last thing a merchant wants to do is put an extra step in front of someone just about to buy.

Re: Japan facing credit card number shortage

#73
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…

There's a risk. Have you ever had your credit card number expire? If a merchant has repeat billing, you don't even need to update with the new date and cvv. Code changes must now be made to make sure I don't end up responsible for someone's else bill because my card expired and someone issued the same card number with a different expiration date and cvv.

Re: Japan facing credit card number shortage

#74

I'd like a unique card number with every transaction, that I set online to exactly the amount I'm spending. And it expires after that one use. Eliminates risk of 'stealing' a credit card, mostly. But it would use a butt-ton of numbers. Maybe a UUID?

I've been doing exactly this for years with Revolut premium (and I'm sure many other "online banks" have the same service). It's like using a password manager, you don't have to worry about how your card details are stored anymore.

It is very neat although I got into strange situations a few times when I needed to prove I was the card owner for a refund or for insurance claims.

Re: Japan facing credit card number shortage

#75

Earlier quoted context omitted.

"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.

Yeah, lots of credit cards does not mean one can use cashless payment everywhere, paradoxically... It's more 5 cards than 15, I admit... I edited my comment accordingly. It still seems a lot to me, why not just one?

I was going to agree it's a lot... but then realised every one of my grocery gift cards has a PAN attached, which means I'm going through 2-3 numbers a month myself. (Not in Japan) Then again, I expect the shop to recycle those faster than Visa.

Re: Japan facing credit card number shortage

#76
post #30

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 stru…

> You can't get 125 million folks into this address space? I think some people are now using a new card number per transaction , with these disposable card numbers, aren't they?

You're talking about services like Google/Apple Pay right? Aren't these credit card numbers rotated by Google/Apple, and they just keep some mapping of userIds, transactionIds, and rotated cardIds?

Re: Japan facing credit card number shortage

#77
post #76

Earlier quoted context omitted.

> You can't get 125 million folks into this address space? I think some people are now using a new card number per transaction , with these disposable card numbers, aren't they?

You're talking about services like Google/Apple Pay right? Aren't these credit card numbers rotated by Google/Apple, and they just keep some mapping of userIds, transactionIds, and rotated cardIds?

No I think you can genuinely get disposable real credit card numbers.

https://www.theukdomain.uk/virtual-credit-card-numbers-every...

Re: Japan facing credit card number shortage

#78
post #67
post #60

Earlier quoted context omitted.

They would need to EOL over-the-phone payments to do this. People have horrible diction and it's hard to tell the difference between b, c, d, and e when a particularly lazy lipped person says these letters (in addition to non-hex letters like g, p, t, and v). Then they use their own ambiguous phonetic system (b as in ball, c as in call, d as in doll will confuse anyone trying to distinguish between the three). Oh and…

Why don’t we teach schoolchildren the NATO phonetic alphabet? Seems like it wouldn’t take that long, and it would be a useful skill for their whole life.

We should. There are so many adults who think it's cute to make up their own phonetics not realizing the whole purpose is to reduce ambiguity, not make it fun to spell things aloud.

Re: Japan facing credit card number shortage

#79
post #30

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 stru…

Your comment is ridiculous. The number has structure, you don't get random IP addresses if you're a company. You get a block, likewise card issuers get a block (BIN - Bank Identifier Number) then add in the checksum, that definitely means you can't just assign random number. Imagine you have a random number. Visa get's the number and a charge for $20. Who owns it? They now have to search through all possible issued c…

My thoughts of this made the parallelism with IP addresses. Japan's issue can be solved by "buying some numbers" from much smaller countries.

The solution to reuse a number is bat shit crazy. Perhaps they can use expired cards (and not cancelled).

In the long run the sensible solution (just like IP addresses) is to move from a "IPv4" system to a "IPv6" that will largely multiply the available numbers per country/bank/entity and will solve the problems, for the next many decades.

Re: Japan facing credit card number shortage

#80
post #57
post #30

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 stru…

Wouldn't the Luhn algorithm checksum [1] limit the available digits? It is specifically there so a one-off error doesn't result in a charge going to a valid other account. [1] https://en.wikipedia.org/wiki/Luhn_algorithm

Most checksum algorithms that I know of for credit card numbers only decrease the number of available digits by 1.

Or equivalently it increases the length by the length of the checksum (usually 1 for credit cards) and doesn't otherwise affect the available numbers.

Post reply on HN