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```Based on a binomial/Poisson distribution and a baseline of 21 million U.S. device sales per release, a fingerprint relying on "seconds since setup" fails to uniquely identify individuals. In the high-density Early Adopter phase, you will share your exact setup second with an average of 1.01 other people (a total matching pool of ~2 people). Six months into the cycle, you will still share that second with an average of 0.68 other people.```

In the U.S., device setup time (to the second) very conservatively gets you clubbed into a single group of 100 individuals as an "advanced persistent threat" tracker. Even compressing activations to "80/20 during business hours" the math kindof maxes out at a pool of ~5 people, and assuming worst case "20x" of that still means you're still pretty darned identifiable.

If you get ~6-8 more bits of entropy (eg: Device Type + Capacity is easily 2-3 bits, and Time Zone is probably another 2-3 bits) you're cooked!

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Reminds me of a meeting I was party to with the Safari team. We worked with them on some standards stuff at an old job. They claimed to have creepy-level tracking of users back then. We were discussing how to identify users for an A/B test across millions of sites and comparing what fingerprints we could both derive to most likely end up on the same user.

If you use a closed source browser. That’s the kinda shit they do.

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Are you claiming the Safari team is fingerprinting their users?
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Just using IP address, device storage, device name, and similar signals, we can identify a user. It isn’t difficult to correlate these data points. Apps like Facebook also force developers to use their SDKs for even small features.
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Yeah, but IP address is "obviously" correlated with a distinct/persistent tranche of users. It's surprising that volume c_time is both more persistent as well as more unique than IP.
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