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The tiny chip that powers Montreal subway tickets

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Re: The tiny chip that powers Montreal subway tickets

#341

Post by zuppy »

solarized wrote: post #334
asah wrote: post #327

Earlier quoted context omitted.

1000s of people leaving a stadium faces the same latency: not a WFH/WFO issue

Haha, absolutely! Just to generalize, those thousands of people can also watch the match by streaming, right? It's all about remote versus physical activities. We can't shift everything into remote mode. However, we don't need to hustle into physical mode every day either. Yeah, yin yang complexity, balancing everything out.

i’m not a sports fan, but the feeling of being there can’t be compared to watching the event from home. this is not the part to optimize, in my opinion.

Re: The tiny chip that powers Montreal subway tickets

#342

Post by BiteCode_dev »

solarized wrote: post #324

To peoples asking: "Why not just QR codes?" Again it's all about latency. QR codes take longer when you tap them at the gate: opening the app, waiting for the scanner to adjust, connecting to inet. While NFC handle these tasks almost instantly. A big difference in super busy places where queues are a nightmare. Again, this problem wouldn't exist if we can optimize WFH methods. We don't need to solving "physical probl…

I can't see big technical limitations resulting in slow QRCode scanning. We manage to detect fast cars going 120mph to fine them, we can read fingerprints instantly through a screen. We can take pictures of galaxies light years away.

30 years ago you could kill ducks with the NES guns instantly and it worked by detecting pixels.

I'm sure we can figure out how to analyze black squares and turn them into a number under 50ms.

Re: The tiny chip that powers Montreal subway tickets

#343

Post by crote »

ForHackernews wrote: post #122

> a per-chip price of nine cents That still seems expensive for a $3.75 metro fare. 2.4% of the cost of your ride is the chip in the ticket itself? Maybe it's worth it because it lets them eliminate mechanical ticket-reading and unify paper tickets with other NFC payment methods.

That's the per-wafer price, via a distributor. I bet you get a decent discount if you buy a few thousand wafers straight from the manufacturer.

Re: The tiny chip that powers Montreal subway tickets

#344

Post by DiogenesKynikos »

grishka wrote: post #288
mav3ri3k wrote: post #284

Earlier quoted context omitted.

I am not sure which part is impractical. In India we already use QR code for metro tickets. The system design is definitely different from one mentioned and mimics more of how airport tickets work.

How does the system know that the ticket was already used? The thing with plane and long-distance train tickets is that you buy them for a specific route. So all the checking only needs to be done at your departure station/airport, the code for which is encoded in the ticket, and the rest of the system doesn't need to know anything about it. But you can't do that with city transport. When there aren't multi-use ticke…

The system can just keep track of whether the ticket has already been used before. You don't have to store the information on the ticket itself. You can store the information on a central server, connected to all the gates.

The ticket itself just has to encode an ID, and then the central database contains an entry for that ID that is checked by the gate in real time. When the ticket is scanned at a gate, the database gets updated.

Re: The tiny chip that powers Montreal subway tickets

#345

Post by abainbridge »

crote wrote: post #335
kens wrote: post #2

Author here for all your NFC chip questions :-)

How do they make the chips so incredibly thin? Surely they're not using 75µm/120µm wafers throughout the entire production process - that's literally the thickness of a human hair! Can a 200/300mm wafer of that thickness even support itself, let alone all the stresses in the production process?

https://en.wikipedia.org/wiki/Wafer_backgrinding

Re: The tiny chip that powers Montreal subway tickets

#346

Post by altacc »

solarized wrote: post #324

To peoples asking: "Why not just QR codes?" Again it's all about latency. QR codes take longer when you tap them at the gate: opening the app, waiting for the scanner to adjust, connecting to inet. While NFC handle these tasks almost instantly. A big difference in super busy places where queues are a nightmare. Again, this problem wouldn't exist if we can optimize WFH methods. We don't need to solving "physical probl…

In some places, like Oslo's metro, tram & bus systems, the solution is that there are no ticket barriers, you're trusted to have bought a ticket for your journey. There are occasional ticket checks with big fines for non-compliance.

Re: The tiny chip that powers Montreal subway tickets

#347

Post by [deleted] »

solarized wrote: post #324

To peoples asking: "Why not just QR codes?" Again it's all about latency. QR codes take longer when you tap them at the gate: opening the app, waiting for the scanner to adjust, connecting to inet. While NFC handle these tasks almost instantly. A big difference in super busy places where queues are a nightmare. Again, this problem wouldn't exist if we can optimize WFH methods. We don't need to solving "physical probl…

[deleted]

Re: The tiny chip that powers Montreal subway tickets

#348

Post by a-dub »

solarized wrote: post #324

To peoples asking: "Why not just QR codes?" Again it's all about latency. QR codes take longer when you tap them at the gate: opening the app, waiting for the scanner to adjust, connecting to inet. While NFC handle these tasks almost instantly. A big difference in super busy places where queues are a nightmare. Again, this problem wouldn't exist if we can optimize WFH methods. We don't need to solving "physical probl…

NYC OMNY allows for direct payment from a debit/credit card via NFC at the turnstile. this has privacy issues but i think they're ameliorated if you use a smartphone.

i think you can buy a transit payment card if you need one.

no paper tickets. cool ephemera but pretty wasteful.

would be pretty cool if/when we see a day where provably private cryptocurrency microtransactions allow for both real privacy and the 7 day fare cap feature.

Re: The tiny chip that powers Montreal subway tickets

#349

Post by hlandau »

G4E wrote: post #188
hlandau wrote: post #73

The NFC chip I want still doesn't exist: a CPU and flash I can write a program for, directly, no VMs, no Java, without an NDA'd datasheet. These exist, but they're all behind NDAs and you're not allowed to have them. They're used for e.g. EMV.

You should check out the lpc8N04 from NXP then ;)

This is interesting but clearly not intended for security/cryptographic applications... no security hardening, no hardware cryptography, and it's also not available in a card form factor according to the datasheet.

Re: The tiny chip that powers Montreal subway tickets

#350

Post by Slartie »

CraigJPerry wrote: post #227

QR codes seem like a better ticket medium. This is like a 100 bytes, a qr code can be over 2kb This is a cheap plastic substrate with ink printing over the top. A qr code is just ink - or some other even cheaper printing process if you prefer. This needs a specific ticket technology supplier over the next 10’s of years. QR codes can be drawn on screens or printed on paper and you can change suppliers for every compon…

I was in Rotterdam recently. Their metro system uses multiple approaches, some kind of RFID for hard tickets, NFC payment (without a ticket at all) and QR codes for time-limited tickets that you can buy in a phone app.

Getting those QR code readers to read the QR code was a nightmare. Almost all the cameras have heavily scratched protective windows in front of them, which makes the reading process a struggle of trying to find a working angle. Of course the scratching is vandalism, but subway systems must be robust against vandalism, cause it's something that happens and must be expected.

I switched to per-transit payment via NFC after using one of the time-limited tickets and realizing that you need to consider yourself lucky if you find just one working QR code reader at most stations. NFC worked like a breeze.

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