11 ms·

Plastic Money

271 points by bertman 3y ago

dna_polymerase 3y ago
PSA: The author of this post also runs a niche YouTube channel that is notoriously under-subscribed. For everyone interested in retro tech & technical infrastructure in the real world, go head over here: https://www.youtube.com/@computersarebad https://www.youtube.com/@computersarebad
- jcrawfordor 3y ago
  "notoriously under-subscribed" is a generous way to put it. I'm going to post a cool video soon though, I swear.
seszett 3y ago
Nice and very interesting write-up. I'd like to comment on this part, about actually writing on cards: > you can create an account online and associate the card with your account, and then you can add value online. This is convenient, but confronts the offline nature of the system. You add value to the card, but there's no way to write the new value to it. > The solution, or at least partial solution, to this problem looks something like this: fare payment terminals have to receive a streaming log of value-add operations so that they can apply them next they are presented with the relevant card. I think that's why new systems often use NFC, since smartphones can do NFC this has the potential (because many NFC transit cards don't allow it yet) to actually charge cards from smartphones. In practice, none of the transit systems I regularly use allow it, and although it's in beta in Paris they only whitelist a handful of specific smartphone models so I can't do it either. But it's a possibility. It could work the same with ISO 7816 smartcards if people just had card readers at home, but in practice here in Belgium where most people have such card readers (used to authenticate online with one's national ID card, although this is becoming less common now that there's a smartphone app for that), this has never been used for anything else basically. And for some reason, smartcard companies seem to be totally unable to devise user-friendly interfaces. It's been more than 30 years now so you might think they have had the time to think about it, but... no. I wish there was just a web standard for that with a standard browser-provided UI.
- dolmen 3y ago
  Charging the Paris transit card (Île-de-France Mobilités) via NFC is out of beta for at least one year now. Much convenient to bypass queues at the start of each month.
- dolmen 3y ago
  > And for some reason, smartcard companies seem to be totally unable to devise user-friendly interfaces. It's been more than 30 years now so you might think they have had the time to think about it, but... no. I wish there was just a web standard for that with a standard browser-provided UI. Browser development is driven from the US. Smartcards development is driven from Europe. I expect that the same frictions that happens in deployment of smartcards for banking also happens in the browsers world.
  - fomine3 3y ago
    Lack of smart card API on browser is quite weird. There are obvious needs by many governments.
- 1023bytes 3y ago
  I've just used this in Malaysia, they have a card called Touch n Go that is very widely accepted. You can load up the card using cash terminals or via a smartphone app with NFC, you can use that to check the balance as well
vinay_ys 3y ago
In more recent times, we had to think about this problem in Indian market context. I saw this problem as online vs offline payments problem. If both parties are offline, can you still make a secure transfer of stored value? Yes, with a trusted execution environment and cryptography, you can do it. So, yeah, smart card works; a smartphone works, a feature phone with NFC smart card works etc. For each, the risk profile is different which affects the answer to the next question. Then, when does reconciliation happen? When either party goes online? What if it is not a closed loop system? Then, reconciliation needs to happen for both parties independently. How long can either party stay offline and continue to make transactions? Is it both send and receive or only send on one side and only receive on another side? What if one party (merchant/receiver) is more likely to be online (almost always). Does it just become online payments problem then? NFC tap and pay is exactly this scenario. In India, right now, we have NETC stored value cards for closed loop systems like metro. For open systems like UPI we have recently introduced offline payments capability with very small stored value stored as tokens on the mobile phone and used for very small transactions. As the banks learn the real-world operational risks, the wallet limits and transaction limits will be increased.
- bertman 3y ago
  >For open systems like UPI we have recently introduced offline payments capability with very small stored value stored as tokens on the mobile phone and used for very small transactions. Sounds interesting! I read about India's UPI for the first time a couple of months ago in an Economist article: https://archive.ph/WoqQp https://archive.ph/WoqQp
- londons_explore 3y ago
  The real solution is to let the receiver of the money have a "verify" button which will, if connected to the internet, contact a central server and check that no double-spends etc. have happened. Up until verification is done, the money shows as "provisional" in your account - but you can still spend it. Only one person in the chain needs to verify for the whole chain to become permanent. Then the users and merchants can decide if they wait to click the verify button. And the default for anyone with data connectivity should probably be auto-verification. There is an incentive to verify, because if any double-spending has happened, the first to verify is the one who gets the money. Double-spends will happen in any system that allows offline transactions, because a user has to be allowed to log into a new device (if they lose their old one), and there is no way to know if the money spent from their old device was synced to the server yet.
kalleboo 3y ago
Wow this discussion unlocked a long-lost memory: the Swedish "cash card" - a stored value card where you'd use a terminal to load money off your bank account onto the stored value card and then use it in participating stores. If you lost the card you lost the money. The fees to merchants were too high so it never gained any adoption, it looks like it only was available from 1997-2004. The Wikipedia references a German version, Geldkarte, which apparently had a renaissance when it could double as proof of age for tobacco vending machines... https://sv.m.wikipedia.org/wiki/Cash_(betalsystem) https://sv.m.wikipedia.org/wiki/Cash_(betalsystem) I'm also reminded of the magstripe stored value cards used by our public transit agency. These were trivial to rewrite, but since most people who tried this did it to save money on their commute rather than random joyriding, it was easy for the agency to reconcile the usage logs to find out where they went every day and wait for them at their station... These days I think the main advantage to offline systems is performance. When you have a busy subway station in Tokyo with massive crowds passing through the gates, nothing beats the throughout of offline Felicia Suica cards. Their gates default to open and you walk through while swiping without stopping, the gates only close if there is a failure. Vs EMV-based systems like London where you have to stop and wait for the card reader
- thatfrenchguy 3y ago
  EMV based systems aren’t necessarily authentification based / don’t always phone home depending on the card issuer.
  - deleted 3y ago
    [deleted]
  - dfox 3y ago
    It depends on both issuer, acquirer and the particular merchant. Second step of the EMV transaction (after the terminal verifies that the card was issued by known issuer) involves the card and terminal comparing their authentication and authorization policies, which might very well result in no-op being acceptable to both. The system is not designed to be secure against fraud, but to assign liability for the fraud to particular party in cryptographically verifiable way. So as a merchant (think public transport) you can very well accept cards offline without any kind of CHV step, but the possible fraud is your problem.
benoliver999 3y ago
This guy writes faster than I can read. I love the site!
robin_reala 3y ago
I spent a few years with a Mondex card[1] (I assume Exeter university was one of the test locations?) and it was vaguely useful: most places on campus accepted it so you could use it to pay for a pint, print or photocopy, or buy course books. Looking through the list of what it could do though it seems it was pretty underutilized. In the test location I was in you couldn’t transfer funds to another person or use multiple currencies, and I don’t remember any personal readers. [1] https://en.wikipedia.org/wiki/Mondex https://en.wikipedia.org/wiki/Mondex
virtualritz 3y ago
I remember getting my first debit card from my local bank in Germany as a teenager. It was in the early 90s, I believe. It had a chip with the ubiquitous brass contacts almost any card has today. My uncle had participated in the patent filings for some of the tech, years earlier, for his employer. He had explained to me, already in the 80s, how this would be the future of carrying money around. It never took off. My personal take is that it was simply an oversight in UX. There was no way to check the balance on the chip without going to an ATM. Furthermore only some ATMs of some banks carried the hardware/software to do so. I also don't recall if you could even check your balance if the ATM belonged to another bank. Also paying by card was far from common in Germany then so few shops carried the readers. It was mostly only big supermarkets and department stores. I.e. it was double inconvenient compared to cash. And Germany being a safe country, the added security in case of theft didn't help. It was also a minor factor since a thieve that would steel your purse would simply throw the card away. The money would be gone either way.
jimmcslim 3y ago
Oh wow, a lot of technology in there from my past... in the late 90's I worked at a startup, Cards Etc, in Sydney, Australia with the mission to build a back-end system, Arterium, for dealing with multi-application smart card issuance. The product is still mentioned in a couple of articles... https://www.afr.com/companies/smartcards-offer-a-world-of-opportunity-20000804-kb72s https://www.afr.com/companies/smartcards-offer-a-world-of-op... https://www.finextra.com/newsarticle/3534/first-data-selects-arterium-from-cards-etc-for-card-management https://www.finextra.com/newsarticle/3534/first-data-selects...
grishka 3y ago
Had to read surprisingly far before there was a mention of transit cards — which is the first thing that comes to mind when I think about stored-value cards. In my city's implementation the offline-ness of the system is very apparent. If you add value to your card online, you have to come to a subway station to stick the card into a reader to have your new balance written. The turnstiles at the same station don't do that either despite definitely having a network connection, you have to specifically use the balance-checking or ticket-selling machines. The only application I've seen that isn't transit is at arcades. You'd buy a "member" card that you'd put money into. Each machine would have some sort of terminal where you tap or swipe that card to add credits to the game. But then I'm not quite sure if these systems are offline or these terminals are connected into a network.
jasmer 3y ago
[dead]
deadeye 3y ago
Am I the only one here that remembers credit cards before they used any sort of online processing? Back in the day, paying with a credit card was a hassle. There was a machine that would take an imprint of your card and you would sign the imprint. There was no authorization.
- fellowmartian 3y ago
  I only know this because of the scene from Home Alone 2.
- elygre 3y ago
  If the amount was big enough, there would be a phone call from the merchant to some call center.
- teh_klev 3y ago
  I'm of that vintage of credit card user that remembers this. I used to keep my counterfoils (I think that's what they were called) to reconcile what was remaining on my available credit. I seem to remember there was a printed list of that some merchants used to look up invalidated cards before electronic terminals replaced mechanical card swipe machines.
  - EricE 3y ago
    I remember my parents credit card bill coming in on punched cards - would have been the mid 70's. Ha!
- andreareina 3y ago
  I used to be the one running those cards through the machine! We actually would call someone (credit card processor?) to give them the details and we'd get an auth code back that we wrote down.
- dghughes 3y ago
  The authorization was the clerk picked up the phone and dialed the credit card company.
- 3y ago
tuetuopay 3y ago
My grandfather was at the head of a French company that pioneered the smart card for banking use. They started with the payphone, continued with the Vitale card (public health system card), then did the credit card. He told me stories of him going in many countries to sell the tech and concept, and this article nails it: this is a French thing, so the US did not want it. They did not want it so badly that magstripe is still commonplace. Its quite nice to listen to him about the beginnings of computing, the notion of "datacenter", etc.
- Chris2048 3y ago
  > this is a French thing, so the US did not want it Given how common US things are in Europe, I'm surprised there isn't more of a trading war over things like this. Personally, I think the EU should penalise foreign all social media companies, and fund local start-ups to replaces them.
  - oaiey 3y ago
    The US is a huge market within, has very revenue focused companies and an active "Homeland security"/national interest management ongoing. I totally believe that the first two points reject 90% of international influence and standardization.
    - Chris2048 3y ago
      I'm not sure I understand what the first two points are. That US corporations are so focused on revenue / a large market that they are not influenced by government? Or that the US market is so big international corps cannot complete (which is irrelevant in the context of my own comment).
      - EricE 3y ago
        Simpler than that - look up the phenomenon known as Not Invented Here
    - jcrawfordor 3y ago
ElongatedMusket 3y ago
Talking up the tech of having physical plastic cards hold value, but ignoring the real-world implications, is kind of silly right? Maybe it would have been better for the author to get that out of the way first... something like "if plastic cards held a value, public figures such as celebrities and CEOs would be robbed, kidnapped, held ransom, etc due to the values of the cards, so they are not practically safe in our non-utopian world. But let's explore the tech behind it anyway"
- lxgr 3y ago
  You’re missing an important point: It’s possible to carry some of your money with you, and leave most of it somewhere more safe, in whatever form, just like with cash.
  - jaclaz 3y ago
    And another important point, public figures tend to have assistants with them that carry the money or the cards or just pay later.
- pjc50 3y ago
  The cards are kind of a cash-substitute.
- kwhitefoot 3y ago
  That's just about the silliest idea I have read this month.
hippich 3y ago
Sometimes back in 90ties, in Belarus, we had payphones that accepted prepaid payphone cards. I don't remember if you could reload them or you just bought one with credits already on them, but you certainly could change a few bytes on the card's chip memory to set credits about to any value you wanted. And the hardest part was actually finding contact board that matched chip's contacts layout, to wire it up to LPT port. But otherwise it was "plaintext" value you change in the hex editor.
- pjc50 3y ago
  The UK had non-chip phonecards for a while: http://www.telephonecardcollector.com/phonecard-collecting-hobby.htm http://www.telephonecardcollector.com/phonecard-collecting-h... I think they were magnetic or magneto-optical?
  - rwmj 3y ago
    Yeah they used a laser to read and burn along a strip in the card. (It was a bit more subtle than I've described it, and you couldn't see the burn mark.)
jeffchien 3y ago
Coincidentally Japan just indefinitely suspended sales of their famous SVCs due to the semiconductor shortage, and BART had issued a similar warning about shortages last year.
reisse 3y ago
We had stored value card payment system in Uzbekistan somewhere from 2003-2005 to 2010-2012. But no-one ever called it "stored value card", basically, I learnt the word today :) Everyone just called it "offline cards", in contrast with "online cards" which required Internet to do transactions. The system was called UzKart (do not confuse with UzCard, which is modern online successor of that system). On the day when salary was paid, you had to find an online ATM or internet-connected terminal in the shop, and "load" money to the card. Then, you could use the money on the card to pay in offline terminals. Balance could be checked directly in offline terminals, you had to ask the seller to print it. Sellers had a special offline card, called "merchant's card". In the end of the day they loaded all the transactions from an offline terminal to a merchant's card, and then brought the card to an ATM or a connected terminal, to synchronize payments with the bank account. If, for some reason, at the time of synchronization some payments failed to clear, payer's card was banned and they had an angry call from the bank. When the system was introduced, internet connection was expensive and unreliable. It co-existed with online cards, but merchants strongly preferred to deal with offline cards. As soon as mobile internet become cheaper and more widespread, offline cards died because of the hassle with "loading" and "unloading" them. More info on UzKart and UzCard can be found (in Russian) here https://gazeta.norma.uz/publish/doc/text97703_uzkart_ot_duet_k_on-line https://gazeta.norma.uz/publish/doc/text97703_uzkart_ot_duet... and here https://uzcard.uz/ru/news/post/uzcard-bankovskaya-tranzaktsiya-ili-kak-rabotaet-vasha-plastikovaya-karta/63 https://uzcard.uz/ru/news/post/uzcard-bankovskaya-tranzaktsi...
- jacobwilliamroy 3y ago
  I'm surprised we don't have something like this in the U.S. Just last week I was withdrawing cash from an ATM because I was worried the power would be out for a few days and my debit card wouldn't work.
  - lxgr 3y ago
    Almost-ubiquitous, almost-free network connectivity can be a curse when it comes to the development of resilient systems. The US has had free local calling for many decades now, so online card authorizations were always much cheaper than in many other countries, even long before the internet. Still, there were some applications: The article mentions laundromats, but as far as I know, US military ships have also had a similar system. There’s an interesting recent legislation proposal today that argues for a very similar system, but primarily for the sake of privacy (although network/power failure resiliency would be nice secondary benefits): https://ecashact.us/ https://ecashact.us/
xn 3y ago
The cafeteria at Visa in San Mateo used smart cards in 1998. There were startups focused on smart cards in the 90s: https://www.nytimes.com/2000/03/24/business/publicard-business-shift.html https://www.nytimes.com/2000/03/24/business/publicard-busine...
sugarkjube 3y ago
I doubt offline cash-like electronic money will ever happen. Like others also already mentioned, we also had a system like this 30 years ago for vending machines and cafeteria in a large corp. Banks want tracking (for customer profiling). Governments wants tracking (for anti-terrorism and anti-money-laundering). So it won't happen.
- esprehn 3y ago
  Consumers also want protection against lost cards, fraud and refunds when the merchant or product is bad.
- kwhitefoot 3y ago
  It happened in 1995 with Mondex, https://en.wikipedia.org/wiki/Mondex https://en.wikipedia.org/wiki/Mondex But I suspect that your reasoning is correct nonetheless.
- paulgerhardt 3y ago
  https://offline.cash/ https://offline.cash/ I mean. It’s already happened. Thanks to some clever non-intuitive use of escrow contracts one can create fungible cash-like electronic money for offline transactions.
- mindslight 3y ago
  The general trend that I see is that institutions [0] will always favor centralization of telemetry and control (eg the concept of legibility). You don't even need to phrase it in the terms of profiling/tracking per se, although those are instances of the general. I think I even feel the same dynamic with something as banal and informal as home automation. With some kind of computer (eg microcontroller) at every node I certainly could keep the local control local. Or I could just focus on publishing data to the "network" [1] and getting commands back, and making the interface a given device exports as simple as possible. We see the results of this harsh dynamic for platforms that allow for hub-less control (eg Zwave I think). Nifty and more robust, but it adds to the bespokeness and siloing/lock-in. It's just so much more complexity that then has to be configured, and then grokked to know what the system will actually do. Whereas backhaul state and control to a general purpose Linux machine running python and you can do "whatever you want" (modulo that singular machine having a problem). Not a great dynamic for those of us that like freedom. [0] or really any entity, corporations and governments can just fulfill the imperative at scale [1] full extrapolation in the corporate context - "cloud"
rtpg 3y ago
I had this for laundry at school in France! I recently was at a US university, and having to use an app and sign up to start my laundry was something awful in comparison (though I liked getting $5 in free credit for some unknown reason)
throwmeaw 3y ago
One of the first stored-value bank cards was called Proton and trialled in Belgium as early as Feb 1995 [0]. I have fond memories as a young teenager topping up the card at my bank ATM (just transferring money from my current account to the proton bit of my debit card) and buying my weekly & monthly computer magazines at the local newsagent. I'm surprised it survived until late 2014, a nearly 20 year long run. [0]: https://en.wikipedia.org/wiki/Proton_(debit_card) https://en.wikipedia.org/wiki/Proton_(debit_card)
- Tijdreiziger 3y ago
  Ha, per Wikipedia, the Chipknip system here in the Netherlands was based on the same technology. Never knew that it was originally Belgian technology.
karmakaze 3y ago
My first encounter was with VendaCard being used in mid-80s at the University libraries for photocopies. Seems they've also been used for autolaundrymats.
nottorp 3y ago
Hmm with cards like these, if they aren't tied to an identity, the general population could print money faster than the governments do.
xyst 3y ago
just a small reminder of how convoluted the process of buyer and merchant payments has become. It used to be simple: - buyer hands the money to the merchant. - merchant verifies monetary value. If monetary value is valid then merchant gives buyer the item. Otherwise, tells them to piss off/get bent. - buyer walks away with item But major credit/debit card processors (visa, mc, amex) had to insert their hands into the pockets of every buyer and merchant to get their 3-5% cut on each transaction. Now it’s a much more complicated process that happens more “seamlessly”: - buyer presents debit or credit card - merchant checks if debit or credit card is accepted by their payment processor —> if not accepted, tell buyer present diff card or “get bent” - merchant swipes/taps/keys-in card information and attempts to process the transaction. A decision is typically reached within less than <1 second —> if declined, try again. If further declined, tell buyer card declined. Buyer insists it’s good and to run it again. Merchant runs it again, it’s successfully processed (wtf?). If not, tell buyer to get bent. - buyer walks away with the item In the background, in order to accept debit and credit cards the merchant had to sign a deal with the devil and pick one of the many payment processors. Merchant could have gone with his bank’s processor but turns out the merchant doesn’t have the right paperwork or lacks the revenue to qualify for a “premium” account. So the merchant looks elsewhere and finds a promising payment processor elsewhere but fails to read the fine print. In addition to the 3-5% fee charged by the major CC networks, the processor will take a 5 cent transaction fee to process, in addition to a 1 cent “inter network” processing fee. ALSO, the “free” equipment that’s provided to your business has a $50 month maintenance fee in perpetuity. On the flip side, if you transact 100K per month, they will cut the transaction fees by 25%, oh how generous! Oh did I forget to mention that some cards have “premium” fees? So if a buyer presents a “black card”, the merchant is then charged by the bank issuing the card another fee. Sometimes it’s included in the payment processing terms but this is YMMV. So as a consumer, if you ever wonder why the small business takes “visa” but not your “chase ultra sapphire pearl max black” card with visa logo. That’s why. Unfortunately, it doesn’t end there. (2 days later) buyer that bought that item actually stole/cloned the credit card and the actual credit card owner initiated a dispute. Merchant has now been charged a $25 dispute fee and is now in the resolution process. If bank and/or credit card processor rules in consumers favor, merchant loses $25 in addition to the cost of the item(s). At the end of the day, merchants get fucked. Merchants pass on costs to consumers/buyers. Buyers get fucked with increased cost of goods. Only winners are the useless middlemen.
pluijzer 3y ago
Starting from 1996 we had ChipKnip in the Netherlands. When it came out you could already pay with debitcards in most shops. The added benefit was that it was suited for small purchases and worked in places without a phoneline, like the bus. One problem is that if you break or lose the card your money will be gone. I remeber that when I was a child more then once I broke my card and had to tape it togheter in aome wild fashion in order to use my money.
miki123211 3y ago
I kind of like the solution adopted by the Polish city of Wrocław (and many others, but Wrocław is the one I'm personally familiar with.) Their transit system relies on bog-standard bank-issued Visa / Mastercard payment cards, the kind most Polish people already have in their wallets. When you buy a ticket (usually at a ticket machine at the stop or in the vehicle itself), the machine temporarily remembers some of your card information. If a ticket inspector comes, you just tap your normal credit / debit card to their terminal, which queries the vehicle's systems somehow. It's basically the reverse of a storage-value system, they use a payment card for a kind of identification. All transactions are performed offline, usually the next day. Tickets are cheap enough that fraud is not a big concern, and there's a system in place to blacklist cards that can't be credited. If you end up on that blacklist, you have to go to their website or office, enter your card number / tap your card and pay the missing amount. If you're a resident and not a tourist, there's also a system of transit cards I believe.
lisper 3y ago
The important point here IMHO is that the vast majority of fraud is not an inevitable cost of doing business, it's the result of deliberate policy decisions, and the fact that the cost of fraud can be fobbed off by financial institutions onto merchants and thence onto consumers without the latter even being aware that they are bearing this cost. It is quite literally a conspiracy.
- deleted 3y ago
  [deleted]
nayuki 3y ago
> SIM cards are just smart cards. [...] SIM cards no longer conform is ISO 7810 in most cases (having migrated to the smaller micro and nano formats), but continue to be compliant with ISO 7816 for electrical and protocol compatibility. Over the past 20 years, I've used mobile cellular telephones that take mini-SIM, micro-SIM, and nano-SIM. I didn't get to experience the full-size SIM card, but learned about this obscure fact from online photos and museums. Example: https://twitter.com/phone_museum/status/1287310071907713024 https://twitter.com/phone_museum/status/1287310071907713024 > Why is it that SVCs gained so little traction for payments in the US? Another obscure point is that during the Bitcoin craze of the mid-2010s, the Canadian government tried to pitch MintChip as a competitor. It fizzled out and went nowhere. https://en.wikipedia.org/wiki/MintChip https://en.wikipedia.org/wiki/MintChip > Offline systems simplify payment networks in some ways, but also add complexity, which is often apparent in transit systems that combine offline terminals (for example in buses) and online terminals (for example at train platforms). [...] If you add value to a card with a zero (or near zero) value and then try to board a bus, it is likely that you will be rejected: the value-add hasn't been written to the card yet, and the bus terminal hasn't been told about it. The transit operator often sets an expectation of one business day for online value adds to be available if your first trip is an offline terminal If you add value to a card with a zero (or near zero) value and then try to board a bus, it is likely that you will be rejected: the value-add hasn't been written to the card yet, and the bus terminal hasn't been told about it. This perfectly describes the situation in Toronto/Ontario with PRESTO, adding value, and tapping on buses.
medler 3y ago
NYC metro cards are reportedly a form of stored-value card. When you swipe, it reads the value, writes the new value, and checks that the correct value was written. Transactions are later synced to a database to catch fraud and so forth. https://www.reddit.com/r/AskNYC/comments/nsicuj/technologically_how_does_a_metrocard_work/ https://www.reddit.com/r/AskNYC/comments/nsicuj/technologica...
- jcrawfordor 3y ago
  NYC MetroCard is yet another Cubic transit SVC system, and so the system is largely identical to other Cubic systems like Clipper, Oyster, etc. As a rule of thumb, most transit card systems in the US and Western Europe are Cubic, but there are plenty of exceptions.
c_o_n_v_e_x 3y ago
Singapore has EZ Link and NETS. Anyone who drives in Singapore would be familiar with NETS as it is the main payment method for car parks (parking garages for my American brethren). NETS has been slowly transitioning from a contact based card (similar to a SIM card) to a NFC/RFID contactless card. Some car parks do NOT accept the new type contactless card which means that you really need to have both flavors of NETS cards when driving.
kccqzy 3y ago
One neat feature of clipper cards I discovered is that they could be transferred onto a smartphone. As a stored value card, I imagine the process involves a smartphone reading the stored value, zeroing it, and then provide a virtualized implementation of whatever the underlying SmartCard technology is (Java Card maybe). The first time I used that feature, I instinctively thought that by adding my clipper card to my smartphone, my smartphone merely has another manifestation of the same clipper card as the original plastic card, much like a credit card but with a special device-specific card number, or like a Unix hard link. Of course I was wrong. The actual card itself was transferred.
pallas_athena 3y ago
> On the smart card, there is a value in nonvolatile memory that represents the amount of money on the card. When you add money, the VTM increments that value. > Of course you can see the problems with this scheme: couldn't anyone just write a bigger number to the card? In my college days we had a vending machine which worked with a NFC card. I bough a NFC reader/writer, and quickly found out that the amount of money was exactly as described above. After a couple of tries I found out that the maximum amount of money was 22€. Free snacks for a couple of years until they changed the machine to accept only cash. No, I'm not ashamed. EDIT: The cards were anonymous, even if the machine somehow tracked the card use (I have no idea if they did), there was not way to trace it back to a person
bilianak 3y ago
Interesting. In Bulgaria we used to have these special prepaid payphone cards as well, it was super convenient, but then smartphones came, of course.

271 points by bertman 3y ago

PSA: The author of this post also runs a niche YouTube channel that is notoriously under-subscribed. For everyone interested in retro tech & technical infrastructure in the real world, go head over here: https://www.youtube.com/@computersarebad https://www.youtube.com/@computersarebad

jcrawfordor 3y ago
"notoriously under-subscribed" is a generous way to put it. I'm going to post a cool video soon though, I swear.

seszett 3y ago

Nice and very interesting write-up. I'd like to comment on this part, about actually writing on cards: > you can create an account online and associate the card with your account, and then you can add value online. This is convenient, but confronts the offline nature of the system. You add value to the card, but there's no way to write the new value to it. > The solution, or at least partial solution, to this problem looks something like this: fare payment terminals have to receive a streaming log of value-add operations so that they can apply them next they are presented with the relevant card. I think that's why new systems often use NFC, since smartphones can do NFC this has the potential (because many NFC transit cards don't allow it yet) to actually charge cards from smartphones. In practice, none of the transit systems I regularly use allow it, and although it's in beta in Paris they only whitelist a handful of specific smartphone models so I can't do it either. But it's a possibility. It could work the same with ISO 7816 smartcards if people just had card readers at home, but in practice here in Belgium where most people have such card readers (used to authenticate online with one's national ID card, although this is becoming less common now that there's a smartphone app for that), this has never been used for anything else basically. And for some reason, smartcard companies seem to be totally unable to devise user-friendly interfaces. It's been more than 30 years now so you might think they have had the time to think about it, but... no. I wish there was just a web standard for that with a standard browser-provided UI.

dolmen 3y ago
Charging the Paris transit card (Île-de-France Mobilités) via NFC is out of beta for at least one year now. Much convenient to bypass queues at the start of each month.
dolmen 3y ago
> And for some reason, smartcard companies seem to be totally unable to devise user-friendly interfaces. It's been more than 30 years now so you might think they have had the time to think about it, but... no. I wish there was just a web standard for that with a standard browser-provided UI. Browser development is driven from the US. Smartcards development is driven from Europe. I expect that the same frictions that happens in deployment of smartcards for banking also happens in the browsers world.
- fomine3 3y ago
  Lack of smart card API on browser is quite weird. There are obvious needs by many governments.
1023bytes 3y ago
I've just used this in Malaysia, they have a card called Touch n Go that is very widely accepted. You can load up the card using cash terminals or via a smartphone app with NFC, you can use that to check the balance as well

vinay_ys 3y ago

In more recent times, we had to think about this problem in Indian market context. I saw this problem as online vs offline payments problem. If both parties are offline, can you still make a secure transfer of stored value? Yes, with a trusted execution environment and cryptography, you can do it. So, yeah, smart card works; a smartphone works, a feature phone with NFC smart card works etc. For each, the risk profile is different which affects the answer to the next question. Then, when does reconciliation happen? When either party goes online? What if it is not a closed loop system? Then, reconciliation needs to happen for both parties independently. How long can either party stay offline and continue to make transactions? Is it both send and receive or only send on one side and only receive on another side? What if one party (merchant/receiver) is more likely to be online (almost always). Does it just become online payments problem then? NFC tap and pay is exactly this scenario. In India, right now, we have NETC stored value cards for closed loop systems like metro. For open systems like UPI we have recently introduced offline payments capability with very small stored value stored as tokens on the mobile phone and used for very small transactions. As the banks learn the real-world operational risks, the wallet limits and transaction limits will be increased.

bertman 3y ago
>For open systems like UPI we have recently introduced offline payments capability with very small stored value stored as tokens on the mobile phone and used for very small transactions. Sounds interesting! I read about India's UPI for the first time a couple of months ago in an Economist article: https://archive.ph/WoqQp https://archive.ph/WoqQp
londons_explore 3y ago
The real solution is to let the receiver of the money have a "verify" button which will, if connected to the internet, contact a central server and check that no double-spends etc. have happened. Up until verification is done, the money shows as "provisional" in your account - but you can still spend it. Only one person in the chain needs to verify for the whole chain to become permanent. Then the users and merchants can decide if they wait to click the verify button. And the default for anyone with data connectivity should probably be auto-verification. There is an incentive to verify, because if any double-spending has happened, the first to verify is the one who gets the money. Double-spends will happen in any system that allows offline transactions, because a user has to be allowed to log into a new device (if they lose their old one), and there is no way to know if the money spent from their old device was synced to the server yet.

kalleboo 3y ago

Wow this discussion unlocked a long-lost memory: the Swedish "cash card" - a stored value card where you'd use a terminal to load money off your bank account onto the stored value card and then use it in participating stores. If you lost the card you lost the money. The fees to merchants were too high so it never gained any adoption, it looks like it only was available from 1997-2004. The Wikipedia references a German version, Geldkarte, which apparently had a renaissance when it could double as proof of age for tobacco vending machines... https://sv.m.wikipedia.org/wiki/Cash_(betalsystem) https://sv.m.wikipedia.org/wiki/Cash_(betalsystem) I'm also reminded of the magstripe stored value cards used by our public transit agency. These were trivial to rewrite, but since most people who tried this did it to save money on their commute rather than random joyriding, it was easy for the agency to reconcile the usage logs to find out where they went every day and wait for them at their station... These days I think the main advantage to offline systems is performance. When you have a busy subway station in Tokyo with massive crowds passing through the gates, nothing beats the throughout of offline Felicia Suica cards. Their gates default to open and you walk through while swiping without stopping, the gates only close if there is a failure. Vs EMV-based systems like London where you have to stop and wait for the card reader

thatfrenchguy 3y ago
EMV based systems aren’t necessarily authentification based / don’t always phone home depending on the card issuer.
- deleted 3y ago
  [deleted]
- dfox 3y ago
  It depends on both issuer, acquirer and the particular merchant. Second step of the EMV transaction (after the terminal verifies that the card was issued by known issuer) involves the card and terminal comparing their authentication and authorization policies, which might very well result in no-op being acceptable to both. The system is not designed to be secure against fraud, but to assign liability for the fraud to particular party in cryptographically verifiable way. So as a merchant (think public transport) you can very well accept cards offline without any kind of CHV step, but the possible fraud is your problem.

benoliver999 3y ago

This guy writes faster than I can read. I love the site!

robin_reala 3y ago

I spent a few years with a Mondex card[1] (I assume Exeter university was one of the test locations?) and it was vaguely useful: most places on campus accepted it so you could use it to pay for a pint, print or photocopy, or buy course books. Looking through the list of what it could do though it seems it was pretty underutilized. In the test location I was in you couldn’t transfer funds to another person or use multiple currencies, and I don’t remember any personal readers. [1] https://en.wikipedia.org/wiki/Mondex https://en.wikipedia.org/wiki/Mondex

virtualritz 3y ago

I remember getting my first debit card from my local bank in Germany as a teenager. It was in the early 90s, I believe. It had a chip with the ubiquitous brass contacts almost any card has today. My uncle had participated in the patent filings for some of the tech, years earlier, for his employer. He had explained to me, already in the 80s, how this would be the future of carrying money around. It never took off. My personal take is that it was simply an oversight in UX. There was no way to check the balance on the chip without going to an ATM. Furthermore only some ATMs of some banks carried the hardware/software to do so. I also don't recall if you could even check your balance if the ATM belonged to another bank. Also paying by card was far from common in Germany then so few shops carried the readers. It was mostly only big supermarkets and department stores. I.e. it was double inconvenient compared to cash. And Germany being a safe country, the added security in case of theft didn't help. It was also a minor factor since a thieve that would steel your purse would simply throw the card away. The money would be gone either way.

jimmcslim 3y ago

Oh wow, a lot of technology in there from my past... in the late 90's I worked at a startup, Cards Etc, in Sydney, Australia with the mission to build a back-end system, Arterium, for dealing with multi-application smart card issuance. The product is still mentioned in a couple of articles... https://www.afr.com/companies/smartcards-offer-a-world-of-opportunity-20000804-kb72s https://www.afr.com/companies/smartcards-offer-a-world-of-op... https://www.finextra.com/newsarticle/3534/first-data-selects-arterium-from-cards-etc-for-card-management https://www.finextra.com/newsarticle/3534/first-data-selects...

grishka 3y ago

Had to read surprisingly far before there was a mention of transit cards — which is the first thing that comes to mind when I think about stored-value cards. In my city's implementation the offline-ness of the system is very apparent. If you add value to your card online, you have to come to a subway station to stick the card into a reader to have your new balance written. The turnstiles at the same station don't do that either despite definitely having a network connection, you have to specifically use the balance-checking or ticket-selling machines. The only application I've seen that isn't transit is at arcades. You'd buy a "member" card that you'd put money into. Each machine would have some sort of terminal where you tap or swipe that card to add credits to the game. But then I'm not quite sure if these systems are offline or these terminals are connected into a network.

jasmer 3y ago

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deadeye 3y ago

Am I the only one here that remembers credit cards before they used any sort of online processing? Back in the day, paying with a credit card was a hassle. There was a machine that would take an imprint of your card and you would sign the imprint. There was no authorization.

fellowmartian 3y ago
I only know this because of the scene from Home Alone 2.
elygre 3y ago
If the amount was big enough, there would be a phone call from the merchant to some call center.
teh_klev 3y ago
I'm of that vintage of credit card user that remembers this. I used to keep my counterfoils (I think that's what they were called) to reconcile what was remaining on my available credit. I seem to remember there was a printed list of that some merchants used to look up invalidated cards before electronic terminals replaced mechanical card swipe machines.
- EricE 3y ago
  I remember my parents credit card bill coming in on punched cards - would have been the mid 70's. Ha!
andreareina 3y ago
I used to be the one running those cards through the machine! We actually would call someone (credit card processor?) to give them the details and we'd get an auth code back that we wrote down.
dghughes 3y ago
The authorization was the clerk picked up the phone and dialed the credit card company.
3y ago

tuetuopay 3y ago

My grandfather was at the head of a French company that pioneered the smart card for banking use. They started with the payphone, continued with the Vitale card (public health system card), then did the credit card. He told me stories of him going in many countries to sell the tech and concept, and this article nails it: this is a French thing, so the US did not want it. They did not want it so badly that magstripe is still commonplace. Its quite nice to listen to him about the beginnings of computing, the notion of "datacenter", etc.

Chris2048 3y ago
> this is a French thing, so the US did not want it Given how common US things are in Europe, I'm surprised there isn't more of a trading war over things like this. Personally, I think the EU should penalise foreign all social media companies, and fund local start-ups to replaces them.
- oaiey 3y ago
  The US is a huge market within, has very revenue focused companies and an active "Homeland security"/national interest management ongoing. I totally believe that the first two points reject 90% of international influence and standardization.
  - Chris2048 3y ago
    I'm not sure I understand what the first two points are. That US corporations are so focused on revenue / a large market that they are not influenced by government? Or that the US market is so big international corps cannot complete (which is irrelevant in the context of my own comment).
    - EricE 3y ago
      Simpler than that - look up the phenomenon known as Not Invented Here
  - jcrawfordor 3y ago

ElongatedMusket 3y ago

Talking up the tech of having physical plastic cards hold value, but ignoring the real-world implications, is kind of silly right? Maybe it would have been better for the author to get that out of the way first... something like "if plastic cards held a value, public figures such as celebrities and CEOs would be robbed, kidnapped, held ransom, etc due to the values of the cards, so they are not practically safe in our non-utopian world. But let's explore the tech behind it anyway"

lxgr 3y ago
You’re missing an important point: It’s possible to carry some of your money with you, and leave most of it somewhere more safe, in whatever form, just like with cash.
- jaclaz 3y ago
  And another important point, public figures tend to have assistants with them that carry the money or the cards or just pay later.
pjc50 3y ago
The cards are kind of a cash-substitute.
kwhitefoot 3y ago
That's just about the silliest idea I have read this month.

hippich 3y ago

Sometimes back in 90ties, in Belarus, we had payphones that accepted prepaid payphone cards. I don't remember if you could reload them or you just bought one with credits already on them, but you certainly could change a few bytes on the card's chip memory to set credits about to any value you wanted. And the hardest part was actually finding contact board that matched chip's contacts layout, to wire it up to LPT port. But otherwise it was "plaintext" value you change in the hex editor.

pjc50 3y ago
The UK had non-chip phonecards for a while: http://www.telephonecardcollector.com/phonecard-collecting-hobby.htm http://www.telephonecardcollector.com/phonecard-collecting-h... I think they were magnetic or magneto-optical?
- rwmj 3y ago
  Yeah they used a laser to read and burn along a strip in the card. (It was a bit more subtle than I've described it, and you couldn't see the burn mark.)

jeffchien 3y ago

Coincidentally Japan just indefinitely suspended sales of their famous SVCs due to the semiconductor shortage, and BART had issued a similar warning about shortages last year.

reisse 3y ago

We had stored value card payment system in Uzbekistan somewhere from 2003-2005 to 2010-2012. But no-one ever called it "stored value card", basically, I learnt the word today :) Everyone just called it "offline cards", in contrast with "online cards" which required Internet to do transactions. The system was called UzKart (do not confuse with UzCard, which is modern online successor of that system). On the day when salary was paid, you had to find an online ATM or internet-connected terminal in the shop, and "load" money to the card. Then, you could use the money on the card to pay in offline terminals. Balance could be checked directly in offline terminals, you had to ask the seller to print it. Sellers had a special offline card, called "merchant's card". In the end of the day they loaded all the transactions from an offline terminal to a merchant's card, and then brought the card to an ATM or a connected terminal, to synchronize payments with the bank account. If, for some reason, at the time of synchronization some payments failed to clear, payer's card was banned and they had an angry call from the bank. When the system was introduced, internet connection was expensive and unreliable. It co-existed with online cards, but merchants strongly preferred to deal with offline cards. As soon as mobile internet become cheaper and more widespread, offline cards died because of the hassle with "loading" and "unloading" them. More info on UzKart and UzCard can be found (in Russian) here https://gazeta.norma.uz/publish/doc/text97703_uzkart_ot_duet_k_on-line https://gazeta.norma.uz/publish/doc/text97703_uzkart_ot_duet... and here https://uzcard.uz/ru/news/post/uzcard-bankovskaya-tranzaktsiya-ili-kak-rabotaet-vasha-plastikovaya-karta/63 https://uzcard.uz/ru/news/post/uzcard-bankovskaya-tranzaktsi...

jacobwilliamroy 3y ago
I'm surprised we don't have something like this in the U.S. Just last week I was withdrawing cash from an ATM because I was worried the power would be out for a few days and my debit card wouldn't work.
- lxgr 3y ago
  Almost-ubiquitous, almost-free network connectivity can be a curse when it comes to the development of resilient systems. The US has had free local calling for many decades now, so online card authorizations were always much cheaper than in many other countries, even long before the internet. Still, there were some applications: The article mentions laundromats, but as far as I know, US military ships have also had a similar system. There’s an interesting recent legislation proposal today that argues for a very similar system, but primarily for the sake of privacy (although network/power failure resiliency would be nice secondary benefits): https://ecashact.us/ https://ecashact.us/

xn 3y ago

The cafeteria at Visa in San Mateo used smart cards in 1998. There were startups focused on smart cards in the 90s: https://www.nytimes.com/2000/03/24/business/publicard-business-shift.html https://www.nytimes.com/2000/03/24/business/publicard-busine...

sugarkjube 3y ago

I doubt offline cash-like electronic money will ever happen. Like others also already mentioned, we also had a system like this 30 years ago for vending machines and cafeteria in a large corp. Banks want tracking (for customer profiling). Governments wants tracking (for anti-terrorism and anti-money-laundering). So it won't happen.

esprehn 3y ago
Consumers also want protection against lost cards, fraud and refunds when the merchant or product is bad.
kwhitefoot 3y ago
It happened in 1995 with Mondex, https://en.wikipedia.org/wiki/Mondex https://en.wikipedia.org/wiki/Mondex But I suspect that your reasoning is correct nonetheless.
paulgerhardt 3y ago
https://offline.cash/ https://offline.cash/ I mean. It’s already happened. Thanks to some clever non-intuitive use of escrow contracts one can create fungible cash-like electronic money for offline transactions.
mindslight 3y ago
The general trend that I see is that institutions [0] will always favor centralization of telemetry and control (eg the concept of legibility). You don't even need to phrase it in the terms of profiling/tracking per se, although those are instances of the general. I think I even feel the same dynamic with something as banal and informal as home automation. With some kind of computer (eg microcontroller) at every node I certainly could keep the local control local. Or I could just focus on publishing data to the "network" [1] and getting commands back, and making the interface a given device exports as simple as possible. We see the results of this harsh dynamic for platforms that allow for hub-less control (eg Zwave I think). Nifty and more robust, but it adds to the bespokeness and siloing/lock-in. It's just so much more complexity that then has to be configured, and then grokked to know what the system will actually do. Whereas backhaul state and control to a general purpose Linux machine running python and you can do "whatever you want" (modulo that singular machine having a problem). Not a great dynamic for those of us that like freedom. [0] or really any entity, corporations and governments can just fulfill the imperative at scale [1] full extrapolation in the corporate context - "cloud"

rtpg 3y ago

I had this for laundry at school in France! I recently was at a US university, and having to use an app and sign up to start my laundry was something awful in comparison (though I liked getting $5 in free credit for some unknown reason)

throwmeaw 3y ago

One of the first stored-value bank cards was called Proton and trialled in Belgium as early as Feb 1995 [0]. I have fond memories as a young teenager topping up the card at my bank ATM (just transferring money from my current account to the proton bit of my debit card) and buying my weekly & monthly computer magazines at the local newsagent. I'm surprised it survived until late 2014, a nearly 20 year long run. [0]: https://en.wikipedia.org/wiki/Proton_(debit_card) https://en.wikipedia.org/wiki/Proton_(debit_card)

Tijdreiziger 3y ago
Ha, per Wikipedia, the Chipknip system here in the Netherlands was based on the same technology. Never knew that it was originally Belgian technology.

karmakaze 3y ago

My first encounter was with VendaCard being used in mid-80s at the University libraries for photocopies. Seems they've also been used for autolaundrymats.

nottorp 3y ago

Hmm with cards like these, if they aren't tied to an identity, the general population could print money faster than the governments do.

xyst 3y ago

just a small reminder of how convoluted the process of buyer and merchant payments has become. It used to be simple: - buyer hands the money to the merchant. - merchant verifies monetary value. If monetary value is valid then merchant gives buyer the item. Otherwise, tells them to piss off/get bent. - buyer walks away with item But major credit/debit card processors (visa, mc, amex) had to insert their hands into the pockets of every buyer and merchant to get their 3-5% cut on each transaction. Now it’s a much more complicated process that happens more “seamlessly”: - buyer presents debit or credit card - merchant checks if debit or credit card is accepted by their payment processor —> if not accepted, tell buyer present diff card or “get bent” - merchant swipes/taps/keys-in card information and attempts to process the transaction. A decision is typically reached within less than <1 second —> if declined, try again. If further declined, tell buyer card declined. Buyer insists it’s good and to run it again. Merchant runs it again, it’s successfully processed (wtf?). If not, tell buyer to get bent. - buyer walks away with the item In the background, in order to accept debit and credit cards the merchant had to sign a deal with the devil and pick one of the many payment processors. Merchant could have gone with his bank’s processor but turns out the merchant doesn’t have the right paperwork or lacks the revenue to qualify for a “premium” account. So the merchant looks elsewhere and finds a promising payment processor elsewhere but fails to read the fine print. In addition to the 3-5% fee charged by the major CC networks, the processor will take a 5 cent transaction fee to process, in addition to a 1 cent “inter network” processing fee. ALSO, the “free” equipment that’s provided to your business has a $50 month maintenance fee in perpetuity. On the flip side, if you transact 100K per month, they will cut the transaction fees by 25%, oh how generous! Oh did I forget to mention that some cards have “premium” fees? So if a buyer presents a “black card”, the merchant is then charged by the bank issuing the card another fee. Sometimes it’s included in the payment processing terms but this is YMMV. So as a consumer, if you ever wonder why the small business takes “visa” but not your “chase ultra sapphire pearl max black” card with visa logo. That’s why. Unfortunately, it doesn’t end there. (2 days later) buyer that bought that item actually stole/cloned the credit card and the actual credit card owner initiated a dispute. Merchant has now been charged a $25 dispute fee and is now in the resolution process. If bank and/or credit card processor rules in consumers favor, merchant loses $25 in addition to the cost of the item(s). At the end of the day, merchants get fucked. Merchants pass on costs to consumers/buyers. Buyers get fucked with increased cost of goods. Only winners are the useless middlemen.

pluijzer 3y ago

Starting from 1996 we had ChipKnip in the Netherlands. When it came out you could already pay with debitcards in most shops. The added benefit was that it was suited for small purchases and worked in places without a phoneline, like the bus. One problem is that if you break or lose the card your money will be gone. I remeber that when I was a child more then once I broke my card and had to tape it togheter in aome wild fashion in order to use my money.

miki123211 3y ago

I kind of like the solution adopted by the Polish city of Wrocław (and many others, but Wrocław is the one I'm personally familiar with.) Their transit system relies on bog-standard bank-issued Visa / Mastercard payment cards, the kind most Polish people already have in their wallets. When you buy a ticket (usually at a ticket machine at the stop or in the vehicle itself), the machine temporarily remembers some of your card information. If a ticket inspector comes, you just tap your normal credit / debit card to their terminal, which queries the vehicle's systems somehow. It's basically the reverse of a storage-value system, they use a payment card for a kind of identification. All transactions are performed offline, usually the next day. Tickets are cheap enough that fraud is not a big concern, and there's a system in place to blacklist cards that can't be credited. If you end up on that blacklist, you have to go to their website or office, enter your card number / tap your card and pay the missing amount. If you're a resident and not a tourist, there's also a system of transit cards I believe.

lisper 3y ago

The important point here IMHO is that the vast majority of fraud is not an inevitable cost of doing business, it's the result of deliberate policy decisions, and the fact that the cost of fraud can be fobbed off by financial institutions onto merchants and thence onto consumers without the latter even being aware that they are bearing this cost. It is quite literally a conspiracy.

deleted 3y ago
[deleted]

nayuki 3y ago

> SIM cards are just smart cards. [...] SIM cards no longer conform is ISO 7810 in most cases (having migrated to the smaller micro and nano formats), but continue to be compliant with ISO 7816 for electrical and protocol compatibility. Over the past 20 years, I've used mobile cellular telephones that take mini-SIM, micro-SIM, and nano-SIM. I didn't get to experience the full-size SIM card, but learned about this obscure fact from online photos and museums. Example: https://twitter.com/phone_museum/status/1287310071907713024 https://twitter.com/phone_museum/status/1287310071907713024 > Why is it that SVCs gained so little traction for payments in the US? Another obscure point is that during the Bitcoin craze of the mid-2010s, the Canadian government tried to pitch MintChip as a competitor. It fizzled out and went nowhere. https://en.wikipedia.org/wiki/MintChip https://en.wikipedia.org/wiki/MintChip > Offline systems simplify payment networks in some ways, but also add complexity, which is often apparent in transit systems that combine offline terminals (for example in buses) and online terminals (for example at train platforms). [...] If you add value to a card with a zero (or near zero) value and then try to board a bus, it is likely that you will be rejected: the value-add hasn't been written to the card yet, and the bus terminal hasn't been told about it. The transit operator often sets an expectation of one business day for online value adds to be available if your first trip is an offline terminal If you add value to a card with a zero (or near zero) value and then try to board a bus, it is likely that you will be rejected: the value-add hasn't been written to the card yet, and the bus terminal hasn't been told about it. This perfectly describes the situation in Toronto/Ontario with PRESTO, adding value, and tapping on buses.

medler 3y ago

NYC metro cards are reportedly a form of stored-value card. When you swipe, it reads the value, writes the new value, and checks that the correct value was written. Transactions are later synced to a database to catch fraud and so forth. https://www.reddit.com/r/AskNYC/comments/nsicuj/technologically_how_does_a_metrocard_work/ https://www.reddit.com/r/AskNYC/comments/nsicuj/technologica...

jcrawfordor 3y ago
NYC MetroCard is yet another Cubic transit SVC system, and so the system is largely identical to other Cubic systems like Clipper, Oyster, etc. As a rule of thumb, most transit card systems in the US and Western Europe are Cubic, but there are plenty of exceptions.

c_o_n_v_e_x 3y ago

Singapore has EZ Link and NETS. Anyone who drives in Singapore would be familiar with NETS as it is the main payment method for car parks (parking garages for my American brethren). NETS has been slowly transitioning from a contact based card (similar to a SIM card) to a NFC/RFID contactless card. Some car parks do NOT accept the new type contactless card which means that you really need to have both flavors of NETS cards when driving.

kccqzy 3y ago

One neat feature of clipper cards I discovered is that they could be transferred onto a smartphone. As a stored value card, I imagine the process involves a smartphone reading the stored value, zeroing it, and then provide a virtualized implementation of whatever the underlying SmartCard technology is (Java Card maybe). The first time I used that feature, I instinctively thought that by adding my clipper card to my smartphone, my smartphone merely has another manifestation of the same clipper card as the original plastic card, much like a credit card but with a special device-specific card number, or like a Unix hard link. Of course I was wrong. The actual card itself was transferred.

pallas_athena 3y ago

> On the smart card, there is a value in nonvolatile memory that represents the amount of money on the card. When you add money, the VTM increments that value. > Of course you can see the problems with this scheme: couldn't anyone just write a bigger number to the card? In my college days we had a vending machine which worked with a NFC card. I bough a NFC reader/writer, and quickly found out that the amount of money was exactly as described above. After a couple of tries I found out that the maximum amount of money was 22€. Free snacks for a couple of years until they changed the machine to accept only cash. No, I'm not ashamed. EDIT: The cards were anonymous, even if the machine somehow tracked the card use (I have no idea if they did), there was not way to trace it back to a person

bilianak 3y ago

Interesting. In Bulgaria we used to have these special prepaid payphone cards as well, it was super convenient, but then smartphones came, of course.