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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

#441

Post by TheRealPomax »

xmcqdpt2 wrote: post #386
Delk wrote: post #374

Earlier quoted context omitted.

I'm not sure that necessarily explains the need for single-use NFC tickets, though. There could be a more durable serial-use or permanent card with NFC that regular commuters could buy, and if those commuters are the vast majority of rush hour passengers, it might not be such a problem if single-use tickets had a slightly slower system. Of course that'd mean having two recognition mechanisms, so the operator might op…

We have those, with two recognition systems. The system the article describes is for the low count, disposable fares (a few tickets or a 3 day pass). Most people in Montreal have a chip card (the OPUS) which is reusable (and 5$ to buy). The OPUS is also super interesting because it's a stored value card that holds the tokens on the card as opposed to a simple ID. The system was developed when cellular connectivity wa…

But why are there disposable tickets at all? Even if you're just visiting, buy a transit card and use it, then get your deposit back when you leave (or keep it as a keepsake).

The idea that you still need single-use tickets for any use-case once you have a working transit card is just bonkers. You don't, stop making them.

Re: The tiny chip that powers Montreal subway tickets

#442

Post by indoordin0saur »

wiz21c wrote: post #439

FTA: > It's remarkable that these NFC chips can be manufactured so cheaply that they are disposable In our times, where we slowly understand that we have problems of resources and waste, I find it very disturbing that "disposable" is considered a positive achievement by the author.

These are so tiny that throwing them away is a drop in the bucket in terms of waste. It's less waste than your morning coffee produces.

Re: The tiny chip that powers Montreal subway tickets

#443

Post by jcynix »

lxgr wrote: post #249
jcynix wrote: post #71

Earlier quoted context omitted.

Single tap cards are usually just used with their "hardwired" chip serial number. That is stored in a central system which invalidates the number once you used it. This makes it rather easy (even if its environmentally unfriendly) to issue these cards: load a number of cards into your machine, register the serial number and invalidate it when used.

That's no longer the case: Many of the newer single-use ticket ICs (including the MIFARE Ultralight one mentioned in the article) actually support data storage and (very) basic cloning protection.

While it is possible to use advanced features from newer chips, I know more than one actual system where they just use the serial number, even when rolling out more advanced Mifare based cards. So your "that's no longer the case" is a bit too general/optimistic IMO.

And sure, simply using the serial number might pose a security risk depending on the application, but that rarely stops implementors to implement such schemes. More often than not do people believe in security by obscurity, sigh. For a simply ticket system the serial number should be secure enought as it is a use-once application.

Re: The tiny chip that powers Montreal subway tickets

#444

Post by grishka »

jazzyjackson wrote: post #383
joenot443 wrote: post #365

Earlier quoted context omitted.

Most North American cities sadly don’t operate at the level of trust required for a system like that to work, as much as I agree it would be better for everyone.

san francisco operates at the level of IDGAF that allows people of all income to ride buses and trams without a ticket

The way you pay for those buses is also kinda ridiculous. You're supposed to know that it costs something like $1.75 and you're supposed to have the exact amount in cash, no change given. But maybe it changed since 2016.

Re: The tiny chip that powers Montreal subway tickets

#445

Post by lwptnsskog »

indoordin0saur wrote: post #442
wiz21c wrote: post #439

FTA: > It's remarkable that these NFC chips can be manufactured so cheaply that they are disposable In our times, where we slowly understand that we have problems of resources and waste, I find it very disturbing that "disposable" is considered a positive achievement by the author.

These are so tiny that throwing them away is a drop in the bucket in terms of waste. It's less waste than your morning coffee produces.

[dead]

Re: The tiny chip that powers Montreal subway tickets

#446

Post by grishka »

woodruffw wrote: post #418
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…

Why would a QR code require Internet, or an app? You could just print it on paper and track the corresponding balance on the server side. To my understanding this is what most transit networks do anyways, to prevent an enterprising user from modifying their balance on the card itself. (The optical scanning argument makes sense, however.)

Even for single-use tickets, the turnstiles on the entire system need to somehow know that you've used your QR code the moment you did it. This requires them all to be connected to some sort of central server. There's a reason why single-use tickets either somehow store the validation mark on the ticket itself (NFC, magnetic stripe, paper that you have to stamp) or get taken away from you (tokens).

> To my understanding this is what most transit networks do anyways, to prevent an enterprising user from modifying their balance on the card itself.

On those on which this was attempted that I know of, this synchronization is far from instant. I was wrong in my other comment, in St Petersburg metro it only takes two hours for a dumped and restored card to be blocked, but you can apparently do this indefinitely on buses and trams because they aren't (weren't?) networked: https://web.archive.org/web/20170323213524/https://habrahabr...

Re: The tiny chip that powers Montreal subway tickets

#447

Post by oopsallmagic »

ghaff wrote: post #358
oopsallmagic wrote: post #194

Earlier quoted context omitted.

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?

Ah, yes. The good old "It's the user's fault for holding it wrong."

[dead]

Re: The tiny chip that powers Montreal subway tickets

#448

Post by steelbrain »

gylterud wrote: post #431
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 would like to point out that there is an implicit assumption here that we actually need a ticket system for public transport. The general concept is “the cost of the price”. Which is something to consider for public goods. If the prices would be zero, the cost of a ticket system would also be zero.

FWIW, even in places like Estonia, which has a free public transport (bus only?) system, the tickets are still sold/used/checked. Reportedly to get usage numbers and to cost-optimize the routes.

Each resident/citizen can buy a public transport card, then tie it to their Gov ID and then tap it everywhere. You could argue that this could be replaced by some vision tech but I guess this is simpler and has dual use (visitors can purchase the card and pay instead of using for free).

Re: The tiny chip that powers Montreal subway tickets

#449

Post by concerned_user »

grishka wrote: post #438
altacc wrote: post #346

Earlier quoted context omitted.

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.

But there still needs to be some sort of validator that you need to use, doesn't it? I've been to two cities with a similar system where you're trusted, Helsinki and Berlin. In Helsinki there are validators that people tap some kind of multiple-trip card on. In Berlin there are very analog paper tickets that you have to put into a "Drucker" on the platform, it stamps it with the date, time, and station name.

It depends if the tickets are trip based or time based, for time based system you don't always need validator.

I have visited Prague in 2019 and their subway had no barriers, ticket machines were tucked somewhere in the corner so that I had to actively look around. Interestingly the metal poles where sticking out of the floor up to waist height with a spacing like that they used to have validators on them before.

Since I had a 3 day ticket and I validated it on the bus when going from the airport I didn't need a validator. Their trams and buses had validators in usual places, so subway probably has them too but not in an obvious place or the ticket machines already print ticket with time on it so you don't need to validate it.

Re: The tiny chip that powers Montreal subway tickets

#450

Post by kergonath »

devmor wrote: post #433
gylterud wrote: post #431

Earlier quoted context omitted.

I would like to point out that there is an implicit assumption here that we actually need a ticket system for public transport. The general concept is “the cost of the price”. Which is something to consider for public goods. If the prices would be zero, the cost of a ticket system would also be zero.

It's kind of silly how contentious this subject is. The majority opinion is that we all pay for public works projects even if they don't benefit us, but for some reason, transit must be self-funded. It's odd, to say the least.

It makes sense if enough people with influence over lawmaking and government have a vested interest in benefiting from “free” infrastructure and some level of friction to use public transit. Add a pinch of “public transit is useless anyway, I have a chauffeur” and here you are.

It is completely counter-productive and damaging to the economy and the environment, but it is not that odd, unfortunately.

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