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Slightly OT, but when migrating data between iPhones, the old iPhone displays an animated point cloud that appears to function like a QR code. You scan it with

Slightly OT, but when migrating data between iPhones, the old iPhone displays an animated point cloud that appears to function like a QR code. You scan it with the new phone, and your data starts to migrate locally through Bluetooth. Other than aesthetics, what are the advantages of the point cloud? Higher bandwidth? Also, if you were to transfer 100s of megabytes of data from device A to B, using A's display and B's camera, what tech would you look into?

Hates_ 6y ago
I could be completely off the mark, but would an animation make it difficult to spoof. I can't now just use a photo of the cloud? Of course it could be that it just looks cool :D
pickledcods 6y ago
Not quite sure I understand what the question is. Calculating the QR is really CPU intensive and the settings on the site are for lowest quality. ANd even now its overloading.
- Jakob 6y ago
  OP asks about Apple’s animated "QR cloud" which was used in some iPhones and with the Apple watch: https://apple.stackexchange.com/questions/301563/what-is-the-technology-used-in-ios-11-settings-migration-moving-blue-dots-par https://apple.stackexchange.com/questions/301563/what-is-the... https://www.quora.com/Has-somebody-tried-to-dynamically-generate-2D-bar-codes-as-particle-cloud-like-the-Apple-Watch-does-during-the-pairing-process-with-the-iPhone https://www.quora.com/Has-somebody-tried-to-dynamically-gene...
dhritzkiv 6y ago
If I had to guess, the animated point cloud isn't tasked with transferring lots of (megabytes) data, but is probably a proprietary version of a QR code, both for aesthetics and security through obscurity. Its format may also have higher information density than a QR code, which would work well for encrypted data. I imagine the heavy lifting is done on Apple's server. The data being transferred locally is likely a GUID/IMEI/etc + a nonce.
- AriaMinaei 6y ago
  Data is actually transferred locally through Bluetooth, but the initial handshake appears to happen through the point cloud.
  - KMnO4 6y ago
    Bluetooth? I would assume direct wifi, ie Airdrop. Use Bluetooth to initiate it but handle the data transfer over high bandwidth wifi
    - yjftsjthsd-h 6y ago
      Why initiate over BT? Wouldn't you bootstrap from QR to WiFi?
joosters 6y ago
I just transferred a friend's iphone the other day and noticed this animated pattern. I presumed the QR-like code was just to transfer authentication so that the two phones could establish a secure wifi connection, since the QR recognition is fairly instantaneous and you don't have to keep the camera on the animation for long. (the process does ask you to keep the phones close, so the later transfer is probably by bluetooth, as you say) One (possible) advantage could be that the animated nature means that someone taking a photograph of the animation won't capture enough data to steal the whole payload? And the use of tiny pixels might mean that even a video capture from anywhere but up-close might not have enough fidelity (after compression) to read the encoding either?
jpttsn 6y ago
I bet its about the “opportunity cost aesthetics”—-Apple thinks QR codes are butt ugly. See also the round App Clips codes recently introduced, and the very late (I bet teeth-grittingly reluctant) introduction of QR scanning in the first-party iOS Camera app.
social_quotient 6y ago
Here is a good demo of a streaming qr solution. Not ours but a good demo of the concept. https://youtu.be/_0djJ1aVEXs https://youtu.be/_0djJ1aVEXs We use a similar method for offline wallet transfers of private crypto keys. I’ll note a couple things. Keep the frame simple and not too dense. Be careful on ecc settings. Higher res camera androids to be slower in our testing. Be ready to loop the series to catch missed frames. Gives your frames and order context. If it’s really sensitive dat, encrypt it before encoding you QR. assume the video can be stolen from a camera. Inject noisy frames To help obfuscate.
- divan 6y ago
  Another animated QR data transfer that uses fountain codes: https://github.com/divan/txqr https://github.com/divan/txqr
  - mleonhard 6y ago
    Did you consider using the front camera for bidirectional phone-to-phone communication? That could allow frame re-transmits which would increase the data rate a lot.
    - divan 6y ago
      That'd be definitely a whole new level, yes, but I think the simplicity of one-way diode communication has its own benefits.
  - throwaway0x00ff 6y ago
    Hey, I wanted to use your library to send data from computer A to computer B, but I don't speak Go yet. How easy would it be to implement a txqr reader for desktop? Piping zbarcam's output could be the easiest way. Have you got any directions for me to do it? It would be a great addition to txqr! Thanks!
    - divan 6y ago
      I'm actually planning to make Go+Flutter application, which will work on iOS/Android, Desktop and Web. Out of curiosity, what's your use case?
dsl 6y ago
> Other than aesthetics, what are the advantages of the point cloud? Higher bandwidth? Higher information density, in that it can pass ad-hoc wifi network info and cryptographic keys. The animated "QR code" also contains a unique code in each frame that is then sent back during the pairing process. This allows them to measure the round trip time from display to camera to wifi back to the original device, preventing relay and replay attacks. (This is based on my attempting to reverse engineer watch pairing for a few days)

Hates_ 6y ago

I could be completely off the mark, but would an animation make it difficult to spoof. I can't now just use a photo of the cloud? Of course it could be that it just looks cool :D

pickledcods 6y ago

Not quite sure I understand what the question is. Calculating the QR is really CPU intensive and the settings on the site are for lowest quality. ANd even now its overloading.

Jakob 6y ago
OP asks about Apple’s animated "QR cloud" which was used in some iPhones and with the Apple watch: https://apple.stackexchange.com/questions/301563/what-is-the-technology-used-in-ios-11-settings-migration-moving-blue-dots-par https://apple.stackexchange.com/questions/301563/what-is-the... https://www.quora.com/Has-somebody-tried-to-dynamically-generate-2D-bar-codes-as-particle-cloud-like-the-Apple-Watch-does-during-the-pairing-process-with-the-iPhone https://www.quora.com/Has-somebody-tried-to-dynamically-gene...

dhritzkiv 6y ago

If I had to guess, the animated point cloud isn't tasked with transferring lots of (megabytes) data, but is probably a proprietary version of a QR code, both for aesthetics and security through obscurity. Its format may also have higher information density than a QR code, which would work well for encrypted data. I imagine the heavy lifting is done on Apple's server. The data being transferred locally is likely a GUID/IMEI/etc + a nonce.

AriaMinaei 6y ago
Data is actually transferred locally through Bluetooth, but the initial handshake appears to happen through the point cloud.
- KMnO4 6y ago
  Bluetooth? I would assume direct wifi, ie Airdrop. Use Bluetooth to initiate it but handle the data transfer over high bandwidth wifi
  - yjftsjthsd-h 6y ago
    Why initiate over BT? Wouldn't you bootstrap from QR to WiFi?

joosters 6y ago

I just transferred a friend's iphone the other day and noticed this animated pattern. I presumed the QR-like code was just to transfer authentication so that the two phones could establish a secure wifi connection, since the QR recognition is fairly instantaneous and you don't have to keep the camera on the animation for long. (the process does ask you to keep the phones close, so the later transfer is probably by bluetooth, as you say) One (possible) advantage could be that the animated nature means that someone taking a photograph of the animation won't capture enough data to steal the whole payload? And the use of tiny pixels might mean that even a video capture from anywhere but up-close might not have enough fidelity (after compression) to read the encoding either?

jpttsn 6y ago

I bet its about the “opportunity cost aesthetics”—-Apple thinks QR codes are butt ugly. See also the round App Clips codes recently introduced, and the very late (I bet teeth-grittingly reluctant) introduction of QR scanning in the first-party iOS Camera app.

social_quotient 6y ago

Here is a good demo of a streaming qr solution. Not ours but a good demo of the concept. https://youtu.be/_0djJ1aVEXs https://youtu.be/_0djJ1aVEXs We use a similar method for offline wallet transfers of private crypto keys. I’ll note a couple things. Keep the frame simple and not too dense. Be careful on ecc settings. Higher res camera androids to be slower in our testing. Be ready to loop the series to catch missed frames. Gives your frames and order context. If it’s really sensitive dat, encrypt it before encoding you QR. assume the video can be stolen from a camera. Inject noisy frames To help obfuscate.

divan 6y ago
Another animated QR data transfer that uses fountain codes: https://github.com/divan/txqr https://github.com/divan/txqr
- mleonhard 6y ago
  Did you consider using the front camera for bidirectional phone-to-phone communication? That could allow frame re-transmits which would increase the data rate a lot.
  - divan 6y ago
    That'd be definitely a whole new level, yes, but I think the simplicity of one-way diode communication has its own benefits.
- throwaway0x00ff 6y ago
  Hey, I wanted to use your library to send data from computer A to computer B, but I don't speak Go yet. How easy would it be to implement a txqr reader for desktop? Piping zbarcam's output could be the easiest way. Have you got any directions for me to do it? It would be a great addition to txqr! Thanks!
  - divan 6y ago
    I'm actually planning to make Go+Flutter application, which will work on iOS/Android, Desktop and Web. Out of curiosity, what's your use case?

dsl 6y ago

> Other than aesthetics, what are the advantages of the point cloud? Higher bandwidth? Higher information density, in that it can pass ad-hoc wifi network info and cryptographic keys. The animated "QR code" also contains a unique code in each frame that is then sent back during the pairing process. This allows them to measure the round trip time from display to camera to wifi back to the original device, preventing relay and replay attacks. (This is based on my attempting to reverse engineer watch pairing for a few days)