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Japan's IC cards are weird and wonderful

aruarian.dance

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Re: Japan's IC cards are weird and wonderful

#171

Post by aidenn0 »

pauldino wrote: post #152
delfinom wrote: post #125

Earlier quoted context omitted.

Yes that is correct. Patents hold it back on Android. Apple just got themselves a licensing deal that apparently lets them just have it on all phones.

The iPhone is really big in Japan (it's one of the few countries where it has a higher market share than in the US) which probably makes it more worthwhile for Apple

I do wonder who it is that has all of these android phones in the US (nearly 40% by the statistics). In my extended friend group only one person other than me uses an Android phone.

Re: Japan's IC cards are weird and wonderful

#172

Post by miki123211 »

I wonder whether it is possible to make a fake card that generates a new key / ID / whatever on each use.

If so, this would completely break the offline part of the system. You couldn't rely on hotlists of known-hacked cards any more, you'd need to check each (new) card with a central system to see if its key was ever actually issued to anybody.

This is assuming there's an actual list of currently issued keys anywhere, if such a list doesn't exist, the whole system would be done for.

The fact that some smartphones can emulate NFC-F doesn't help either. If a hacking technique is ever discovered, we can get from the system being fully secure, to anybody being able to issue themselves undetectable cards for any amount, in the matter of days.

With counterfeit physical cards, you can at least try to shut down manufacturers and issue long prison sentences to the dealers selling them on the black market. The criminal activity has to happen in the country where the cards are used by definition, so that country can bring its law enforcement to bear. If all you have is an Android apk and some source code released by three guys in Russia, there's very little you can do.

If such a system were designed in the 2020s, you could establish a CA-like system, where each card's key must be signed by a chain of certificates. This way, thoroughly hacking just one card wouldn't help, as its key could easily be revoked, and you couldn't issue new ones without hacking the (presumably airgapped) card manufacturing systems that contain the signing keys. I don't think a system from the late '80s does this, though.

Re: Japan's IC cards are weird and wonderful

#173

Post by ValentineC »

aidenn0 wrote: post #171
pauldino wrote: post #152

Earlier quoted context omitted.

The iPhone is really big in Japan (it's one of the few countries where it has a higher market share than in the US) which probably makes it more worthwhile for Apple

I do wonder who it is that has all of these android phones in the US (nearly 40% by the statistics). In my extended friend group only one person other than me uses an Android phone.

> I do wonder who it is that has all of these android phones in the US (nearly 40% by the statistics).

I'm guessing it's largely the working class and undocumented immigrants. And probably lots of burner phones?

Re: Japan's IC cards are weird and wonderful

#174

Post by nayuki »

umbra07 wrote: post #170
nayuki wrote: post #162

Earlier quoted context omitted.

That is quite interesting. I took normal-speed medium-distance trains in Taiwan and there are many similarities to Japan. The ticket-checking gates to enter/exit the station are exactly the same models used in Japan. The tickets are similar to the ones used in Japan, but they have a QR Code printed on them and might not be magnetic. Even when you exit the station, the ticket gate will give back your ticket - unlike J…

Oh really? The two dmeo videos I just saw of the Japanese system seemed to give back your ticket as soon as you walked through the gate.

The normal ticket gate behavior in Japan is that when you enter, the gate gives you the ticket back so that you can carry it all the way to the exit in order to prove that you traveled that journey. When you go through a ticket gate to exit the station, all Japanese ticket gates to my knowledge will dispose of your ticket.

Re: Japan's IC cards are weird and wonderful

#175

Post by sejin8642 »

AshamedCaptain wrote: post #55

I don't understand -- we are talking about 100ms or so of latency? which is almost completely dwarfed by any mechanical action such as the gates actually opening?? This is about as ridiculous as it gets. The videos that compare the UK system with the JP system practically show the same throughput, even when in the UK video most people are using magnetic/paper tickets (which by necessity are going to be much slower th…

I understand your criticism since it seems that you never visited Japan, Tokyo specifically, before. The train/subway entrance gate is open by default. So if your ticket or IC card or phone didn't get registered properly because you don't have enough fund, the gate closes. And there are a lot of people that use the metro during rush hours, and when I said a lot, I mean it is basically a sea of people flowing through. And when those people are trying to get onto the platform, you want to make sure they walk past through the gates like they are just walking on street. Very fast scan with open gate makes it possible. You don't wait at the gate because you don't have to wait for ticket scan and gate door opening.

Also, if you use an iPhone (i don't have any experience with Android phone in Japan so I can't speak for it) to scan, you don't have to unlock the phone to use it. You simply reach into your pocket to grab your phone, and put the phone near the gate scanner as you approach the gate, and it scans instantly really fast (I was actually surprised how fast it was compared to the ones in Seoul). The experience feels like you are just walking through a narrow passage without any hindrance.

I also like your suggestion to remove the gates. When I visited Germany and Austria I really liked the subway there (no gates, and it even operates past midnight!). I saw only one ticket inspector out of probably about 20 subway rides when I was there, but it seems to work just fine. I am afraid such system might be abused in countries like Korea or China.

add: I also just realized that no gate system wouldn't work in Japan or Korea because during rush hour there is no way for ticket inspector to check the tickets of passengers on train. You are squeezed in each train unit like sardines squeezed in tin can.

Re: Japan's IC cards are weird and wonderful

#176

Post by AshamedCaptain »

socalgal2 wrote: post #166
AshamedCaptain wrote: post #97

Earlier quoted context omitted.

I find this a very thin argument, even thinner than the one coming from the authorities claiming rampant ticket fraud. I travel by train a shitton through all of Europe, and I have _never_ had the issue of boarding a train without knowing if I had a valid ticket for it. And even in the cities w/o gates there is some expectation that you will have to validate the ticket somewhere, at your leisure. Do you ever board st…

> I travel by train a shitton through all of Europe, and I have _never_ had the issue of boarding a train without knowing if I had a valid ticket for it. Like I said, I was used to Japan. I couldn't have boarded a train without passing through a gate for which I would have needed a ticket. As pointed out above, that happened in Paris. At no point between the metro and the train was their any barrier preventing me fro…

Yes, slowing down native users of public transportation because of tourists is a big, popular movement in places like Paris. /s

To transform your argument: why do my partially-disabled relatives now need to walk by themselves to their train seats? Just so that people who don't even read the instructions do not make a mistake that is going to result in a slap on the wrist fine (if anything, cause few revisors are going to fine you if you look touristy enough) ?

The only thing I keep hearing is how having no barriers at all is just intrinsically better, and difficulties with getting used which such system look like very minor compared to the difficulties with moving from a system with no barriers to a system with barriers, not mentioning the disadvantages for users.

Re: Japan's IC cards are weird and wonderful

#177

Post by soruly »

lxgr wrote: post #90
pwim wrote: post #5

Unfortunately transit operators are looking to discontinue the use of these IC cards in favour of QR codes as part of a cost saving strategy: https://mainichi.jp/english/articles/20241015/p2a/00m/0bu/01...

I believe QR codes are mostly intended to replace paper/magnetic single-ride tickets, not IC cards, in most transit systems. Magnetic tickets are already slower than IC cards, and are both more expensive to produce and harder to recycle than QR codes printed on regular paper.

Yes, I believe so. JR East is now planning to fade-out magnetic tickets by using paper QR Code tickets.

Re: Japan's IC cards are weird and wonderful

#178

Post by ValentineC »

lxgr wrote: post #128
jddj wrote: post #122

Earlier quoted context omitted.

Is nfc via google/apple wallet faster then?

Apple Pay uses hardware secure elements, so the same limitations largely apply. Google Pay emulates the card on the application processor, so theoretically it could be faster, but I wouldn't be surprised if anything won in terms of more performant RSA cryptography is lost to higher command processing latency between the NFC interface and application processor. It would be interesting for somebody to do a latency comp…

Doesn't Google Pay offload some of the processing to their cloud?

Google Pay only allows a certain number of offline transactions (around three or so, I think) before I'm required to turn off airplane mode and authenticate with their servers.

I believe this also allows it to work with more phones, and get around security and possibly also regulatory requirements, since there's less need for a really secure secure enclave on NFC devices.

Re: Japan's IC cards are weird and wonderful

#180

Post by soruly »

kirici wrote: post #148

I've recently returned from a trip across the country and liked everything about my (physical) ICOCA card, except that the machines used to charge it, at least the ones I've found, only accepted cash. After charging it once with a decent balance though, I got away (almost) entirely without cash using it in combination with a virtual credit card via NFC, save for street food carts and Gachapon machines.

There are charging machines that accept cash cards / debit cards, but only those issued by Japanese banks. So cash is the only option for touristists. You can go completely cash-less if you can use mobile Suica / ICOCA, which let's you charge your phone with Apple Pay / Google Pay (with osaifu-keitai).
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