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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

#221

Post by lxgr »

Tijdreiziger wrote: post #110
ck45 wrote: post #70

Earlier quoted context omitted.

This reminds me a bit of Nabaztags, or maybe the reverse. They would also read something that resembles NFC and could perform an action.

Around that time, I recall there being a lot of hype around RFID tags. E.g. the Touchatag was just a bunch of RFID tags and a USB RFID reader, but marketed as a consumer product. This never really seems to have caught on, though. Nowadays, I suppose most consumers do have RFID tags (debit cards, transport cards, building keys, e-Passports), they just might not be aware of the underlying technology.

Given that these things are essentially QR codes via another medium, I'm not surprised that it never caught on: QR codes are much cheaper to make (it costs nothing to include them on a leaflet other than some extra ink/toner!) and basically serve the same purpose.

Where they make more sense is when they actually include dynamic information: Some of the newer tags can e.g. include an authentication tag in the URL part, which lets you verify the tag's authenticity (together with a web service that keeps track with the high watermark of opened sequence numbers).

I wouldn't call that "RFID" anymore, though; to me, RFID means transmitting only an identifier, with all the logic happening on the backend, but ISO 14443 tags get most interesting/useful when they go beyond that and do things like authentication or local processing.

Re: The tiny chip that powers Montreal subway tickets

#222

Post by inkyoto »

lxgr wrote: post #171
Sytten wrote: post #108

They are going away soon (TM), the tech is cool but they are impractical. I will be happy to use my credit card or phone. Too many times I have been stuck in 15-20 minutes queues to buy those tickets and you cant refill them with an app... Plus south shore and north shore have they own system it's a mess.

I agree in that they are much more convenient for tourists and occasional users, but when living in a city and taking public transit every day, I actually prefer stored-value cards, as there are still some advantages that arguably make them a better fit for the transit use case: - Full offline support (i.e. both the reader and payment device don't need network connectivity), making the system more resilient - Symmetr…

> I agree in that they are much more convenient for tourists and occasional users […]

I would argue that contactless debit/credit card or mobile wallet taps are substantially more convenient for tourists and occasional users – if you are fresh off the boat (or off the plane – for a more modern twist), not much can beat the convenience of turning up at the turnstile, tapping on and getting on with the trip on the local public transport network and tapping off at the end of the trip.

No need to look for a place that sells local rechargeable or disposable NFC cards, having to be aware of a low balance, looking for a place where the card can be topped up, actually top them up and stuff like that. For frequent travellers, it also entails having fewer non-portable mass transit payment cards to carry.

Bonus points: debit/credit card/mobile wallet payments also eliminate the problem of the discovery and consolidation of lost balances when a card gets lost, and it reduces the environment impact (manufacturing + energy consumed during the process) and the wastage (the disposal or, rather, the lack thereof) that disposable NFC cards inherently possess.

That is what Sydney (the one that is not in Canada) has done: they went straight from prepaid paper tickets to their own rechargeable Octopus/Oyster style cards (with the name also beginning with an «O» – Opal) followed by enabling debit/credit card (Visa/MC/AmEx) and mobile wallet NFC payments later within the larger metropolitan area public transport network on buses, ferries, trains and trams.

Convenience, as always and of course, comes at the expense of privacy, though.

Re: The tiny chip that powers Montreal subway tickets

#223

Post by lxgr »

Charon77 wrote: post #217

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

Magnetic paper can't do computations, so these tickets are a storage medium only and as such can usually be trivially copied. That puts higher requirements on the backend's availability in order to prevent fraud.

Most people in Japan actually use (reloadable) IC cards, as far as I understand, and railways seem to be in progress of switching magnetic stripe tickets for QR code based ones: https://english.kyodonews.net/news/2024/05/362243d2c187-japa...

Re: The tiny chip that powers Montreal subway tickets

#224

Post by lxgr »

inkyoto wrote: post #222
lxgr wrote: post #171

Earlier quoted context omitted.

I agree in that they are much more convenient for tourists and occasional users, but when living in a city and taking public transit every day, I actually prefer stored-value cards, as there are still some advantages that arguably make them a better fit for the transit use case: - Full offline support (i.e. both the reader and payment device don't need network connectivity), making the system more resilient - Symmetr…

> I agree in that they are much more convenient for tourists and occasional users […] I would argue that contactless debit/credit card or mobile wallet taps are substantially more convenient for tourists and occasional users – if you are fresh off the boat (or off the plane – for a more modern twist), not much can beat the convenience of turning up at the turnstile, tapping on and getting on with the trip on the loca…

Yeah, that's what I meant, sorry if that wasn't clear – open-loop payment card based systems make more sense for infrequent users and tourists for all the reasons you've mentioned; dedicated card purse-based systems can be better for regular commuters.

Re: The tiny chip that powers Montreal subway tickets

#225

Post by lxgr »

Reason077 wrote: post #184
kccqzy wrote: post #141

Earlier quoted context omitted.

It is theoretically possible to refill it with the phone. You either have a stored value card where the value is stored on the card and have the phone's NFC talk to it, or you store the value in a server that has an API to add value and have the reader at the subway deduct the value from the server.

That’s exactly how online top-ups, and credits/refunds, work with the Oyster card system. In the old days you’d nominate a specific station, and the credit would be transferred to the card the next time you tapped in at that station. But now days I don’t think you need to do that: presumably it maintains the balance primarily on the server side now rather than on card.

I think Oyster cards are still stored-value based, but I suspect that either the backend servers and connections are now fast enough to poll pending top-ups in real time, or they just fan out the pending top up dataset to all turnstiles.

I remember using that feature in the SF bay area, and while it took a day for the top-up to actually propagate to all readers, it even worked on buses, so they must be uploading that data everywhere.

That type of connection needs to be there in any system that supports lost/stolen card value recovery, in any case, since that's how card block lists are distributed.

Re: The tiny chip that powers Montreal subway tickets

#226

Post by selcuka »

marssaxman wrote: post #69
justusthane wrote: post #21

This is fascinating. We were just in Europe where we experienced these tickets for the first time. I had trouble with them; I was trying to figure out how to scan them because it never occurred to me that they might contain an NFC chip. My wife, on the other hand, who is not at all technical, took it for granted that you would tap them and immediately figured it out intuitively.

That's funny - I'm sure I would have shared your confusion, as all tappable objects in my world are made of plastic. I wonder how your wife thought of it?

> I wonder how your wife thought of it?

Probably because it's around the size of a credit card and has fake smart card contacts printed on it. That being said, I would probably get confused myself too.

Re: The tiny chip that powers Montreal subway tickets

#227

Post by CraigJPerry »

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 component - from mobile phone apps to paper type to physical printer and reader devices - until your heart’s content over the next years. That flexibility can’t be underestimated in a space like public ticketing over decades.

Issuing replacement tickets needs physical presence to collect the ticket, vs qr code which can be emailed, sent on whatsapp, shared as a screenshot or photo if you need to, but of course you can still exchange physical paper qr codes if you prefer.

The rfid reader for these are cheap and durable, the optical reader for qr codes can be almost as cheap and almost as durable but not quite, the rfid wins this one point by a small margin.

Re: The tiny chip that powers Montreal subway tickets

#228

Post by s0rce »

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…

RFID is less angle dependent on reading well quickly. There are delays boarding planes trying to get everyones phone to scan while the NFC seems to work a bit better just hold it up to the reader and walk through.

Re: The tiny chip that powers Montreal subway tickets

#229

Post by landedgentry »

randunel wrote: post #138
chgs wrote: post #123

Mifare is what’s been used in London’s Oyster cards for 20 years (not the ultralight ones mind), and Hong Kong for even longer. However oyster really is in its way out for most uses. contactless and especially a phone is far more convenient for non season use, and far less wasteful.

There's a noticeable delay between contactless cards and oysters. Some people I know prefer oyster cards simply because they open the gates faster, in spite of having to top them off all the time. I'm looking forward to not having to choose one trade-off over the other.

The MIFARE protocol (which Oyster cards use) takes 300ms to 500ms per tap. EMV (i.e. contactless cards) take ~500ms, which slows down normal walking speed.

Here's a good summary of NFC protocols used for transit gates: https://atadistance.net/2020/06/13/transit-gate-evolution-wh...

The Felica standard is fastest at 100ms per tap, and is used in Japan (e.g. Suica card) and Hong Kong (Octopus card).

Re: The tiny chip that powers Montreal subway tickets

#230

Post by grishka »

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…

The problem with QR codes is that they are read-only.

I don't know about Montreal, but Moscow public transport uses similar paper tickets, also Mifare Ultralight, except you can get them for different number of trips. When you use your ticket, the turnstile or validator would increment those one-way counters so that the next one would know how many trips you have left. You can't do that with a QR code without either the reader or the user's device having a persistent internet connection to some sort of central server that would keep track of all tickets, which is impractical.

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