4 ms·
With one hash, that would obviously be impossible. With millions? Trivial... Particularly when you already know the phone numbers for many of the users (those w
by JshWright 10y ago
With one hash, that would obviously be impossible. With millions? Trivial... Particularly when you already know the phone numbers for many of the users (those who have added their number to their profile), and you can match against contact databases.
- xapata 10y agoIf you're going to cheat by using your contacts database, why not just ask your colleague for the original data? Even with hundreds of millions of observations, the space of possible hashing algorithms that map phone numbers onto those hash codes is infinite. Well, not infinite, but the space of functions that map phone numbers onto whatever domain the hash codes have is mind bogglingly large.