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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

#61
You can use these around the house or car for location-tap automation. Tap on NFC tag and mobile phone can trigger a custom shortcut for local action or SSH script to Linux SBC or micro PC. Response time is about one second. Even the iPhone SE2 has an NFC reader.

For vision-impaired people, NFC tags can be attached to objects and the phone can read an audio description when the object is tapped against phone.

Re: The tiny chip that powers Montreal subway tickets

#62
post #33

> There are multiple NFC standards with differences in speed, protocol, and range, including NFC-A, NFC-B, NFC-C, NFC-F, and NFC-V. The MIFARE Ultralight cards use NFC-A, which is defined by the standard "ISO/IEC 14443 Type A". Pet peeve: Calling these chips "NFC" is a bit misleading. NFC-A isn't defined by ISO 14443-A, but builds on it. NFC is an umbrella standard that defines a way of storing structured data on a w…

>NFC is an umbrella standard that defines a way of storing structured data on a wide variety of existing contactless IC technologies [...]

Yeah, then it's appropriate to call this NFC.

Re: The tiny chip that powers Montreal subway tickets

#63
My favorite household NFC usage? NFC alarm clock.

Makes me get out of bed and tap my phone on a specific NFC tag placed somewhere around the house, in order to turn off the alarm. Then, I may as well wake up, since I'm already out of bed : )

It's a nice companion to help perform 'habit stacking' as Atomic Habits calls it. Want to do pushups right after waking up? Place an NFC card under your workout mat, so you're forced to the mat first thing in the morning.

NFC Alarm Clock https://play.google.com/store/apps/details?id=com.nfcalarmcl... is a really great and simple Android alarm. Share if anyone has a good iOS recommendation.

Re: The tiny chip that powers Montreal subway tickets

#65
post #54

Earlier quoted context omitted.

In general, the card emulation devices (e.g. the chips in phones) try to avoid letting any arbitrary UID be set. This makes cloning these cards more difficult than it would otherwise be. It’s not terribly difficult to find devices (USB-connected things and battery-less cards) that do allow arbitrary UIDs to be set, though.

> the card emulation devices (e.g. the chips in phones) try to avoid letting any arbitrary UID be set. I can't think of a much worse way to do security. That feels like trying to flood the market with lockpicks that don't work instead of making a more pick-resistant lock.

I imagine this is because the locks contain chips from NXP (PN532 chips), the name-brand MIFARE chips are made by NXP, and the lock picks (also PN532 chips!) are made by NXP.

Re: The tiny chip that powers Montreal subway tickets

#66

Comparing Montreal subway with Vancouver's skytrain: - Montreals subway stations have this gritty, distinctively french atmosphere i loved it. - Vancouvers above/below stations have no soul, distinctively anglo but above ground ones i liked. - Montreal train cars use rubber wheels to my shock! Extremely loud. - Vancouver train cars use some sort of electric system which im not familiar with ( have a few variants (new…

In addition to how hosting the Olympics hurt Montreal financially, there was substantial tax revenue loss from the trend of corporate headquarters moving from Montreal to Toronto staring in the 1960s due to Francophone policies.

Re: The tiny chip that powers Montreal subway tickets

#67
post #46
post #19

Earlier quoted context omitted.

I haven't really looked into the security aspects. I think that you could clone one of the Ultralight chips, but it wouldn't gain you anything because the security is in the backend. It's a lot like a printed concert ticket or boarding pass. You could print as many as you want, but the ticket is still good for just one admission. The DESFire and other secure chips contain a cryptographic key that you can't access. Wi…

Ultralight supports password authentication, and you can diversify the password from the serial number, meaning that until that password is revealed by a legitimate reader as part of a validation transaction (at which time the ticket is invalidated anyway), you can't clone it. Ultralight C does support actual cryptographic authentication.

I don't think the password authentication helps against cloning. You could start a transaction and stop after you get the password. Then you could clone the card. (The system could invalidate the ticket as soon as they get the UID, but that would be a reliability nightmare since a failure during the read would invalidate someone's ticket.)

Re: The tiny chip that powers Montreal subway tickets

#68
post #33

> There are multiple NFC standards with differences in speed, protocol, and range, including NFC-A, NFC-B, NFC-C, NFC-F, and NFC-V. The MIFARE Ultralight cards use NFC-A, which is defined by the standard "ISO/IEC 14443 Type A". Pet peeve: Calling these chips "NFC" is a bit misleading. NFC-A isn't defined by ISO 14443-A, but builds on it. NFC is an umbrella standard that defines a way of storing structured data on a w…

>NFC is an umbrella standard that defines a way of storing structured data on a wide variety of existing contactless IC technologies [...] Yeah, then it's appropriate to call this NFC.

Except that the highest layers in that stack is not used by many contactless systems. As an analogy, you wouldn't call HTTP or TCP "web protocols" either, even though the web uses both (but it can also run on QUIC, which is UDP, and you can do non-web-things via HTTP).

Importantly, NFC standardizes a way of storing structured data like URLs or phone numbers on NFC tags; transit tickets most likely don't use tags in that way.

Re: The tiny chip that powers Montreal subway tickets

#69

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?

Re: The tiny chip that powers Montreal subway tickets

#70

You can use these around the house or car for location-tap automation. Tap on NFC tag and mobile phone can trigger a custom shortcut for local action or SSH script to Linux SBC or micro PC. Response time is about one second. Even the iPhone SE2 has an NFC reader. For vision-impaired people, NFC tags can be attached to objects and the phone can read an audio description when the object is tapped against phone.

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