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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

#261

Post by Reason077 »

lxgr wrote: post #225
Reason077 wrote: post #184

Earlier quoted context omitted.

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…

The Oyster card balance is certainly maintained online in real-time (or near to real-time) since you can view it in the Oyster card app/website.

But yes, for speed/redundancy they are still probably using the stored value balance too.

Re: The tiny chip that powers Montreal subway tickets

#262

Post by inkyoto »

lxgr wrote: post #242
inkyoto wrote: post #234

Earlier quoted context omitted.

> […] dedicated card purse-based systems can be better for regular commuters. I suppose it is a matter of personal or circumstantial preferences so I won't go into that, but through reading this discussion, I have learned that, e.g. the Boston MTBA's CharlieCard, have an expiry date and has to be replaced in person . From the regular commuter's point of view it is a nuisance of epic proportions – to turn up at a bus…

Mobile wallets are not a contradiction to dedicated transit cards, though! Apple Wallet supports transit cards for dozens of transit systems, and most of them have some associated app to allow managing monthly passes or topping up the balance. Arguably, that's the best of both worlds.

Yes, I am in a full agreement on the best of both worlds, with a couple of caveats.

Apple Wallet supports neither the Montreal (the subject of this discussion) nor Boston CharlieCard transit cards nor many more. Apple Wallet has promptly shown some transit cards from mainland China, 1x from France, 1x from Hong Kong, 3x from Japan and only 3x (!) from the US (Clipper, SmarTrip and TAP). That is all it supports. Android may support more.

The said CharlieCard[0] supports a bespoke mTicket app that is neither integrated with the mobile wallet nor fully supports all modes of transportation in Boston:

  √ Best for Commuter Rail and ferry riders who don’t often take the subway or bus
  ∅ No transfers to other modes
Which brings me to the main caveat. Compared to debit/credit card payments originated in a mobile wallet, supporting each transit card in existence is an extra effort that places the onus at least on the vendor of the mobile operating system and usually on the local government as well. Generally, governments do not have a good track record at delivering modern digital solutions to their citizens and are inefficient at engaging the smartphone vendors. So at the very least, the governments are slow to instigate a technological change.

And, since the onus is also on the government to upgrade NFC readers across the entire network anyway – to support modern ways of paying, the question is which one is more future proof: 1) natively supporting a local transit card at the smartphone level + upgrade the NFC readers to support a variety of NFC protocols, or 2) upgrade the NFC readers to support the debit/credit card and mobile wallet payments only? I am inclined to think that (2) is more efficient and more cost-effective for taxpayers.

[0] https://www.mbta.com/fares/charliecard

Re: The tiny chip that powers Montreal subway tickets

#263

Post by jFriedensreich »

kens wrote: post #2

Author here for all your NFC chip questions :-)

as always a delight to read ken! im curious about speculation how to do the bonding and mounting of these chips at scale. at this size even the general handling and cutting of wafers are hard to imagine for me. how did the connections to the antenna look like and was there an indication of different glue / adhesive layers apart from the coatings you described?

Re: The tiny chip that powers Montreal subway tickets

#264

Post by tjohns »

chii wrote: post #256
grishka wrote: post #230

Earlier quoted context omitted.

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…

it would be interesting to create a wipe mechanism to erase the existing QR code (may be a belt/sander, or a laser like those rust cleaning lasers), and print a new one on (may be even use the same laser as the wipe!).

IC transit cards in Japan use heat-rewritable ink for something similar.

The ticket vending machines print your monthly transit passes right onto the face of your card at the beginning of the month, and erase it after it expires.

It's not a QR code though. Just human readable text for bus drivers. (Turnstiles in the subway still read the pass via NFC.)

Re: The tiny chip that powers Montreal subway tickets

#265

Post by jszymborski »

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…

My understanding is that the STM (runs the Métro) likes to keep fares on the actual paper tickets or rechargeable card, rather than in some central database.

The paper tickets can hold many fares, including unlimited evening fares or two day fares. I believe this would be hard to pull off with QR codes without having to keep track centrally.

Re: The tiny chip that powers Montreal subway tickets

#266

Post by Fej »

grishka wrote: post #230
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…

NJ Transit uses QR codes for all train tickets and it works well enough. It's not quite as seamless as a tap card but NJT has moved largely to mobile ticketing and they're in the odd position of having to scan tickets both at turnstiles and by train crew (handheld scanners); cards would be awkward in the latter case. The paper tickets used to have magstripes but once they adopted QR codes for the mobile app, the tickets lost the magstipe and gained a printed QR code.

So the central server model is practical. The user's device has to have an internet connection at some point to activate the ticket within a reasonable period before using it but the connection doesn't have to persist after that. I don't know how their handheld scanners work in the Hudson River tunnels where there is no cell service but they do, so long as the user activates their ticket before the train departs.

Re: The tiny chip that powers Montreal subway tickets

#267

Post by [deleted] »

jszymborski wrote: post #265
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…

My understanding is that the STM (runs the Métro) likes to keep fares on the actual paper tickets or rechargeable card, rather than in some central database. The paper tickets can hold many fares, including unlimited evening fares or two day fares. I believe this would be hard to pull off with QR codes without having to keep track centrally.

[deleted]

Re: The tiny chip that powers Montreal subway tickets

#268

Post by jszymborski »

kens wrote: post #104
teruakohatu wrote: post #99

Earlier quoted context omitted.

That was a god read, thank you. Do you have any insight into the economics of this in general compared to other disposable solutions. Are manufacturing old school magnetic stripe tickets, or just optical scanning/barcodes a lot cheaper? I imagine magnetic stripes have a higher failure to read rate at the turnstile causing issues, while both them and optical scanning requires the ticket to be inserted into the machine…

I couldn't find a nice price breakdown. I'd expect the magnetic stripe tickets to be cheaper to manufacture, but since the NFC tickets cost pennies, there isn't a lot of money to save. I agree with you that magnetic stripes would have a much higher maintenance cost due to the mechanical aspect and the read/write head. Optical scanning seems less likely to work the first time, based on my experience with airplane chec…

FWIW, Montreal used to have mag strip paper tickets and turnstiles to match, but ever since the new paper tickets rolled out we have new svelte turnstiles with an NFC reader exclusively.

They've been trying to get contactless bank card payments going on the same turnstiles but roll-out has been bogged down by other transit agencies apparently.

Re: The tiny chip that powers Montreal subway tickets

#269

Post by jszymborski »

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.

> you cant refill them with an app

You can now refill the rechargeable OPUS cards using an app.

Re: The tiny chip that powers Montreal subway tickets

#270

Post by jszymborski »

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…

Montreal has mostly followed this trajectory, be we haven't yet stuck the landing yet on bank cards. Most turnstiles now are equipped to handle them but the project has stalled a bit.
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