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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

#491

Post by [deleted] »

mardifoufs wrote: post #159
kens wrote: post #93

Earlier quoted context omitted.

Strangely enough, I used the ticket in the article for the REM train (from Du Quartier, where I was staying).

Yeah the Montreal area transport system uses the opus system (the disposable cards are part of that) for everything. Sadly, it's now bizarrely more complicated with the weird zones that they recently added after half a decade of consultations that were meant to... stream line intercity travel! for example, if you take the metro in Montreal, then ride it until Laval, you have to buy a specific type of ticket with the…

[deleted]

Re: The tiny chip that powers Montreal subway tickets

#492

Post by CraigJPerry »

ak217 wrote: post #466
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…

Lots of others mentioned key downsides of QR codes that make them generally unsuitable for this purpose (they are stateless, trivially copied, easily fouled from repeated use, too slow because of fundamental optical constraints, require a 100% available centralized ledger/don't work while the reader is offline, etc. etc.) but I'd just point out that decades of R&D have gone into making these systems work well at scal…

Is that a paper from 2005 about a system designed in 1997? History is excellent for research but in the decades since, many things have changed.

Some of those downsides are positives (immutable, easily copied) others aren’t accurate, for example here’s the Mumbai metro in 2023 with qr entry gates https://youtube.com/shorts/TxbEgEzY9J8?si=s3gE-7_xbCbDoQ1d

Or that a 100% available central ledger is needed (it’s not).

That Qr code systems are in use today in some of the busiest locations would probably be the most succinct counterpoint though.

Re: The tiny chip that powers Montreal subway tickets

#493

Post by CraigJPerry »

esskay wrote: post #332
stavros wrote: post #313

Earlier quoted context omitted.

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

Its slow because it's read by a camera. That takes extra steps, and like you mention, lighting conditions. A QR code has to be detected, read and decoded, and thats after the image is processed. An NFC is orders of magnitude faster. Heck even an old school magnetic strip is faster than a QR code. A better application for QR codes is scenarios where it doesnt matter that its slower. Airline checkins, concert tickets,…

When I travel to work, the time from me rotating my phone screen to present it to the qr reader window on the gate until the time that the gate opens is Separately we have revenue enforcement patrols with handheld scanners. The time from the red flash of the scanner on my screen (triggered by the person holding the scanner, it’s not constantly scanning) until the beep for ticket result is < 200ms, I.e. it feels very much almost instant but with a little perceptible delay.

Re: The tiny chip that powers Montreal subway tickets

#494

Post by bunderbunder »

hgomersall wrote: post #490
bunderbunder wrote: post #478

Earlier quoted context omitted.

NFC doesn't necessarily create any additional e-waste. In Chicago we have an NFC system, and people typically just link their phone to their account and use that to pay. I still use a physical card - so that I have a backup option in case something happens to my phone - but even there the volume of waste is trivial. I've had my current transit card for ages, and it doesn't expire until 2037. It's possible that the on…

Well, yes, but the article is about a disposable nfc ticket.

Those are more for single rides by people who rarely or never use the transit system. I've had the same Carte Opus for years and just bring it with me and refill whenever I visit Montreal. And the disposable paper cards are being phased out. I'm not sure when the rollout will be, but Montreal is currently working on upgrading the system to allow people to just tap-to-pay at the turnstiles using their phones or compatible credit and debit cards.

Which is not something that you could do with a QR system. I don't know that anything is inherently wrong with QR codes, but they do seem to be a choice that's more appropriate for countries like China where the existing electronic payment infrastructure uses QR codes. In North America, by contrast, things have generally settled on NFC, and I think that that reason alone probably makes NFC the better option for North American transit systems.

Re: The tiny chip that powers Montreal subway tickets

#495

Post by seabass-labrax »

ghaff wrote: post #391
seabass-labrax wrote: post #212

Earlier quoted context omitted.

£165.90, to be precise (anytime single). Or, if you travel late-morning to early-afternoon, £70.20 (super off-peak single). By booking weeks or months in advance, you can travel for as little as £22.50 (advance single). The unofficial BR Fares[1] website does a lot to untangle the complexity, although it can only do so much to mitigate the expense. [1]: https://www.brfares.com/

Making purchases ahead varies quite a bit across Europe. The UK seems to fall pretty hard on the you really should buy well in advance side or you're going to pay through the nose. I used to work with someone who, even on an expense account, would roll their eyes if someone wanted them to do a last minute trip to London.

Indeed! Travelling last-minute, you could even be 'quids in' by popping over to the continent for an afternoon so that you'd be eligible for an Interrail ticket:

  4-Day Interrail Global Pass, Adult passenger:    €283
  Eurostar seat reservation (any destination) x2:  €060
                                                 = €340 (~£288)
Nearly fifty pounds less than the price of two Leeds London Anytime Single fares, £331.80! And since hotel rooms in London aren't cheap either, you might even save money by staying the night in Lille rather than London. Kings Cross is part of the same station complex as the Eurostar departures at St. Pancras, so you would save money, spend less than three additional hours travelling and not even risk getting rained on.

This is Hacker News, but even still, I feel kind of icky suggesting a 500-kilometre detour to save money on a journey between two British cities no further than that distance from each other. How I wish we could just have a British version of the Austrian 'climate ticket' and leave all of our inscrutable rail fares behind us!

Re: The tiny chip that powers Montreal subway tickets

#496

Post by Aeolun »

seabass-labrax wrote: post #212
Aeolun wrote: post #204

Earlier quoted context omitted.

“Make the damn train work” is not a local custom. Aside from that the UK rail system is so complicated and expensive you’d expect a manned gate at every station at the least. £150 from London to Leeds?! I can fly halfway across Europe for less…

£165.90, to be precise (anytime single). Or, if you travel late-morning to early-afternoon, £70.20 (super off-peak single). By booking weeks or months in advance, you can travel for as little as £22.50 (advance single). The unofficial BR Fares[1] website does a lot to untangle the complexity, although it can only do so much to mitigate the expense. [1]: https://www.brfares.com/

I’m used to traveling the same distance for around £40 regardless of the time I book (shinkansen).

I guess it’s too bad I can’t save money on booking in advance, but on the other hand, I can easily jump on the train at any point of the day without sticker shock.

Re: The tiny chip that powers Montreal subway tickets

#497

Post by markus_zhang »

lukan wrote: post #166
markus_zhang wrote: post #98

Earlier quoted context omitted.

I have found the same thing with my wife. I'm a technical person, but I'm extremely bad with tools and such, including the ticket thing. If no one shows me how to use it I'll probably figure out a way to insert it somewhere. My wife won't have any problem with this and other small tools. The same thing with IKEA: I always rely on the manual and just blindly follow the instructions, and gets very frustrated if the ins…

"I always rely on the manual and just blindly follow the instructions, and gets very frustrated if the instructions miss one step" But why do people make incomplete manuals? If I have a step by step guidance and it doesn't work, because some steps were left out, than this is just a wrong manual! (I share your frustration)

Some instruction booklets are completely BS. I recently tried out a Coleman 8-people tent and the booklet is just a 4-picture page. The official setup video on YouTube is less than 2 minutes...

I mean, it's completely useless for people who has zero experience with camping -- exactly the people who need those instructions and videos and exactly the people who buy these types of tents from Costco.

Re: The tiny chip that powers Montreal subway tickets

#498

Post by lxgr »

abhayhegde wrote: post #471
lxgr wrote: post #190

Earlier quoted context omitted.

Apple and Google achieve the same outcome (i.e. something called "card emulation", where an NFC chip can act as an emulated ISO 14443-4 smartcard), but they achieve it through very different ways: Google just has an Android API for it called HCE (Host Card Emulation), and anybody can write an app that implements it (i.e. Google Pay has no special position compared to competitors). In a nutshell, you just get a callba…

Is it possible that the Android implementation could be less secure given the lack of a dedicated secure element? Perhaps not, but I am curious why Apple does it that way.

It's definitely less secure for issuers: The entire point of having a secure element is that the issuers of digital wallet cards and passes can't trust all of their users to not decompile their app and extract a private key that grants fraudsters infinite money or transit rides. Physical cards and secure elements on the other hand are resistant against key extraction even in an adversarial environment.

There are ways to mitigate that in software (e.g. by not ever loading long-lived keys into software, fetching them just in time after device attestation etc.), but while that works pretty well for the kind of payments where the terminal needs to be online anyway, it's very risky for offline transactions.

That's why Suica and most other stored-value passes only support iPhones and a handful of specific Android devices that have a secure element (or can use the SIM card as one).

Re: The tiny chip that powers Montreal subway tickets

#499

Post by grishka »

DiogenesKynikos wrote: post #483
grishka wrote: post #451

Earlier quoted context omitted.

That server would have to process thousands of requests per second during a rush hour with very little delay. In addition to QR codes just being much more finicky than tapping a card or sticking something into a slot.

It only has to process requests inside a single station, and then periodically sync up with a central server. This doesn't sound difficult at all.

This is indeed how systems around the world do it for NFC tickets. The problem with QR codes is that they're very easy to copy, so the potential for abuse with this approach is much higher. What's to stop people from using the same ticket on two different stations within the sync period?

Re: The tiny chip that powers Montreal subway tickets

#500

Post by efreak »

bunderbunder wrote: post #494
hgomersall wrote: post #490

Earlier quoted context omitted.

Well, yes, but the article is about a disposable nfc ticket.

Those are more for single rides by people who rarely or never use the transit system. I've had the same Carte Opus for years and just bring it with me and refill whenever I visit Montreal. And the disposable paper cards are being phased out. I'm not sure when the rollout will be, but Montreal is currently working on upgrading the system to allow people to just tap-to-pay at the turnstiles using their phones or compat…

> Montreal is currently working on upgrading the system to allow people to just tap-to-pay at the turnstiles using their phones or compatible credit and debit cards. > Which is not something that you could do with a QR system

I've got several apps that display QR codes on the screen for an external reader. One of them is for my health insurance id card (a simple 10 digit number), another shows my COVID vaccination status (this one is complicated, and I'm not sure why they used a QR code for it. It must include batch identification and other information given the size)

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