4 ms·

Did you read about it? This isn't that.

tengbretson 7y ago
What part? Deriving location from contact tracing is trivial. The fact that its being discussed as opt-in? If participating in society requires that you "opt-in" then what about it is really opt-in?
- CubsFan1060 7y ago
  The part about how it works. Once you've read that (here's a link: https://covid19-static.cdn-apple.com/applications/covid19/current/static/contact-tracing/pdf/ContactTracing-CryptographySpecification.pdf https://covid19-static.cdn-apple.com/applications/covid19/cu...) Can you describe to me how you'd track individuals with it?
  - tengbretson 7y ago
    For starters, I would assume that most people's daily rotating keys could easily be fingerprinted based on identifiable patterns of movement that could be picked up by any number of municipal devices people come into contact with throughout the day. In order for contact tracing to work as advertised, each person's device has to keep a log of daily ids that they contacted that has a TTL of at least a few weeks. That means that whenever a law breaker gets arrested, law enforcement would be able to confiscate their device and be able to construct a list of everyone that they've been in contact with in the last few weeks.
    - tastroder 7y ago
      The Daily Tracing Key cannot be "easily fingerprinted" since it does not leave the device (see page 5). Your LE threat model seems like grasping at straws, the majority of users already have location services enabled anyway, people breaking the law would have to change exactly nothing from the common practice of not bringing your phone when committing crimes.
      - tengbretson 7y ago
        I miss-spoke. I meant to say the rolling proximity identifier could be tracked and fingerprinted. Furthermore, it's not the same as a phone's location implicating you in a crime. It's a persistent log of your in-person social network that can be reverse engineered every time you get arrested or go through customs at the airport.
        tastroder 7y ago
        The rolling proximity identifier is short-lived and put through a non reversible cryptographic hash function to prevent exactly that, same page. You're not going through airports in a pandemic, after which you can uninstall whatever app you're using in this crisis.
- FabHK 7y ago
  I know on HN we are not supposed to allege that someone hasn’t read TFA, but please, could you read the spec and then give some details on how to (“trivially”) derive location from the contact tracing as described?

What part? Deriving location from contact tracing is trivial. The fact that its being discussed as opt-in? If participating in society requires that you "opt-in" then what about it is really opt-in?

CubsFan1060 7y ago
The part about how it works. Once you've read that (here's a link: https://covid19-static.cdn-apple.com/applications/covid19/current/static/contact-tracing/pdf/ContactTracing-CryptographySpecification.pdf https://covid19-static.cdn-apple.com/applications/covid19/cu...) Can you describe to me how you'd track individuals with it?
- tengbretson 7y ago
  For starters, I would assume that most people's daily rotating keys could easily be fingerprinted based on identifiable patterns of movement that could be picked up by any number of municipal devices people come into contact with throughout the day. In order for contact tracing to work as advertised, each person's device has to keep a log of daily ids that they contacted that has a TTL of at least a few weeks. That means that whenever a law breaker gets arrested, law enforcement would be able to confiscate their device and be able to construct a list of everyone that they've been in contact with in the last few weeks.
  - tastroder 7y ago
    The Daily Tracing Key cannot be "easily fingerprinted" since it does not leave the device (see page 5). Your LE threat model seems like grasping at straws, the majority of users already have location services enabled anyway, people breaking the law would have to change exactly nothing from the common practice of not bringing your phone when committing crimes.
    - tengbretson 7y ago
      I miss-spoke. I meant to say the rolling proximity identifier could be tracked and fingerprinted. Furthermore, it's not the same as a phone's location implicating you in a crime. It's a persistent log of your in-person social network that can be reverse engineered every time you get arrested or go through customs at the airport.
      - tastroder 7y ago
        The rolling proximity identifier is short-lived and put through a non reversible cryptographic hash function to prevent exactly that, same page. You're not going through airports in a pandemic, after which you can uninstall whatever app you're using in this crisis.
FabHK 7y ago
I know on HN we are not supposed to allege that someone hasn’t read TFA, but please, could you read the spec and then give some details on how to (“trivially”) derive location from the contact tracing as described?