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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

#311

Post by grishka »

mav3ri3k wrote: post #304
grishka wrote: post #288

Earlier quoted context omitted.

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…

Fair enough. I went through qr code of my previous metro ticket to see what info they encode. It is non standard so there were - some hashes - type of ticket, in my case single use, - time of issue, - valid upto time, approx 10hrs, approx journey time was only 30 min - ticket id - I could not directly see source/destination address, but it is my hunch that atleast the destination address is encoded Now this one time…

Thinking of it, QR codes make sense for when you buy a single-use ticket at the station with the intention to use it immediately.

We actually have this for suburban trains, it's just a receipt with a 1D barcode on it. You use the barcode to open the turnstile (on some stations where they are installed), but otherwise the tickets are checked by controllers that occasionally go through trains.

For getting around a city though, I don't see much of a good use case. In my city, if you're here for at least several days, you're expected to buy the refillable card. If you're only here briefly and only need to use the metro a couple times, it's 1.5x more expensive but you'd buy tokens or tap with your bank card.

Re: The tiny chip that powers Montreal subway tickets

#312

Post by esskay »

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…

QR Codes are fine for one off event entries. For a transport medium that requires fast high volumes of people to go through its an awful idea. QR Code reading is slow, you can't avoid that.

Re: The tiny chip that powers Montreal subway tickets

#313

Post by stavros »

esskay wrote: post #312
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…

QR Codes are fine for one off event entries. For a transport medium that requires fast high volumes of people to go through its an awful idea. QR Code reading is slow, you can't avoid that.

Why is it slow? And is it still slow in perfect lighting conditions?

Re: The tiny chip that powers Montreal subway tickets

#314

Post by stavros »

The_Colonel wrote: post #305
CraigJPerry wrote: post #293

Earlier quoted context omitted.

1. Thats ok. If you’re expecting your rfid tokens not to be copied just because it seems inconvenient to do so, you’re in for a surprise! Your ticketing system cannot assume tickets in any form cannot be replicated- they can be and if you introduce such a vulnerability in your system, you will lose revenue 2. As per 1, no issue 3. That’d be a great feature if true, I’m all for immutability. However , qr codes can be…

> Your ticketing system cannot assume tickets in any form cannot be replicated- they can be and if you introduce such a vulnerability in your system, you will lose revenue Yes, the question is not whether such system would be abused, but how much. But this is in the end what businesses care about. Will QR codes be abused more than NFC chips? Likely yes. Will it produce a larger financial loss than the cost of the NFC…

A centralized system is how tags work already, so you can't toss your ticket to your friend behind you and have them reuse it.

Re: The tiny chip that powers Montreal subway tickets

#315

Post by Ekaros »

oopsallmagic wrote: post #194
ghaff wrote: post #149

Earlier quoted context omitted.

It's getting better but, in my experience, once metro systems got away from manned booths and tokens, the systems worked fine for commuters but led to lots of fumbling and long lines for tourists. Trains in the UK still have a certain amount of "Which of these tickets/receipts go where?" while a line of irritated locals is building up behind you. Fortunately, also being the UK, someone will help you if you're struggl…

Is that the fault of the system, or the fault of the tourists for visiting a new place and not reading up on local customs?

Poor UI is poor UI. Recently visited system which supports contactless payment. So the terminal is there. And it has arrow to left with logo of contactless payment. Logically first thought is that you just swipe card from right to left over it right? No keeps failing, is something wrong with my card? Also other card does not work...

In the end assholes designing it hid the payment terminal in such way that you can't see it from usual angle of use.. Amazingly hostile user design for those that rarely use that transport system...

Re: The tiny chip that powers Montreal subway tickets

#316

Post by numpad0 »

Charon77 wrote: post #217

I wonder why they don't use magnetic paper instead like how Japan is using? Seems cheaper

Those electro-mechanical ticket readers are borderline lost technology and sadly don't belong in this software-eletronic era

0: https://www.youtube.com/watch?v=3Vn-QxQOoqQ

Re: The tiny chip that powers Montreal subway tickets

#317

Post by teknologist »

rswail wrote: post #289
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've worked in public transport ticketing for the past 30 years including the first system outside Japan (Hong Kong's Octopus). The problem with QR codes: 1. If they're printed, they can be copied. 2. "Dynamic" QR codes can be screenshot. 3. They're read-only (by definition) 4. Readers are slow, require good orientation by the user. NFC is good because it's read/write, has a ~10cm range, the larger cards can hold up…

I’ve found NDEF cards that can hold 16KB & 32KB, even as much as 64KB. That may be too much capacity for ticketing but it blows QR codes out of the water

Re: The tiny chip that powers Montreal subway tickets

#318

Post by Ekaros »

kalleboo wrote: post #260

I recently learned that you can just give a printing company a hundred bucks or so and have custom NFC cards printed for you, you don't actually have to be a big transit agency with an ongoing contract for millions of the things and a custom JavaCard NFC application or w/e coded for you. I used this knowledge to replace the QR code membership card to my friend's bar with an NFC card version, it looks really cool in y…

You can even get blank cards, I have a few from university days. And you can get card printer... Can't find exact price now, but not extremely priced. In theory you could just do whole thing in single location from coding the card to printing it, even with custom information.

Re: The tiny chip that powers Montreal subway tickets

#319

Post by teknologist »

grishka wrote: post #275
karunamurti wrote: post #272

Earlier quoted context omitted.

Once I searched how Japan do the synchronization of the data in the IC card because I can't imagine how they handle all of the traffic for millions of people especially in the rush hour. So the solution is the transportation card is writable, and each train station acts like a small data center. They sync the data periodically to the main data center. I think the syncing tech is getting better, Japan train companies…

> So the solution is the transportation card is writable, and each train station acts like a small data center. They sync the data periodically to the main data center. That's also how the two subway systems I'm most familiar with do it here in Russia. In both Moscow and St Petersburg, the data stored on the refillable tickets (Troika and Podorozhnik respectively) was thoroughly reverse engineered. People who did it,…

Oyster in London works like this too so I’ve heard. Some terminals (e.g. those on buses) are offline until the terminal is docked and connected to the main centre.

Re: The tiny chip that powers Montreal subway tickets

#320

Post by kwhitefoot »

Teever wrote: post #24
kwhitefoot wrote: post #23

Earlier quoted context omitted.

Assuming that it doesn't become litter on the street what is the actual impact of such waste?

All of the waste that went into producing it of course. IC fabrication produces a lot of chemical waste, and I would imagine that these ICs aren't fabbed in a place that has a great track record on pollution.

These devices are so tiny that presumably this is also a tiny part of IC fabrication.

I'm not saying there is none, just trying get an idea of how much of a problem this really is. We also need to consider what impact any alternative solution would have.

What struck me from the description of the system was that it seems that no electronics is really needed at all, a unique QR or barcode would be just as good because the back end system records the use.

But that would require the installation of optical readers in a system that might not have them but does already have NFC readers. Adding those readers would add a considerable amount of e-waste too.

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