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Bots can do credit card transactions today, generate selfies that would fool automated detection (unless you are having humans in the loop, in which case they c

Bots can do credit card transactions today, generate selfies that would fool automated detection (unless you are having humans in the loop, in which case they can easily generate them cheaper than they are to verify and ddos you that way), and pretend to be friends once 5 real people have vouched for them. Having an older gmail is going to do a good job making sure only the millenials and their botnets get in today, but also plenty of real customers in most domains will be blocked. All of these might work today just because they aren’t widely used yet. Once they are and are understood they’ll be cracked. The government oauth is maybe the most interesting; it probably just kicks the can to a government site which is going to have all the same problems, but could potentially benefit from a secure national id. But now the government has a database of all the sites you are logging into; forget privacy of library records, that’s a massive loss to the 4th amendment in practice. No need for prism or other NSA exploit nonsense when sites are literally pinging a government server to verify citizen network activity.

microtonal 3y ago
Why? Put a signing key pair on a secure element (e.g. in the passport). Let the government sign the public key. This way sites can check if it’s a government-approved keypair. You can prove that you own the key pair using the private key. No site ever has to contact the government for authentication. The only issue is that it could lead to cross-site tracking because you are reusing the same public key everywhere. But maybe cryptography experts have a solution?
- jlokier 3y ago
  > But maybe cryptography experts have a solution? They do! The field of zero-knowledge cryptography targets exactly this sort of use case, proving things to a recipient without revealing other things. In this case, you might send a zero-knowledge proof that you have the private key corresponding to a government-signed public key, without revealing either key and, importantly, without communicating with the government or sending correlatable information on each transaction. (If you were ok communicating with the government you could just get it to sign a random public key for each transaction without needing zero-knowledge cryptography). You can do a lot more, for example proving "I am 18+ [attested by gov signature]" without revealing your age, birthday or identity, or "I have security clearance level 2 [attested by gov signature]" without revealing anything else, or "I have a driving license [attested by gov signature] and current paid-up insurance [attested by insurer signature]" etc. The field has advanced technically a lot in the last few years, to the point that those sorts of zero-knowledge proofs are now easy to implement technically and reasonably fast to compute.

microtonal 3y ago

Why? Put a signing key pair on a secure element (e.g. in the passport). Let the government sign the public key. This way sites can check if it’s a government-approved keypair. You can prove that you own the key pair using the private key. No site ever has to contact the government for authentication. The only issue is that it could lead to cross-site tracking because you are reusing the same public key everywhere. But maybe cryptography experts have a solution?

jlokier 3y ago
> But maybe cryptography experts have a solution? They do! The field of zero-knowledge cryptography targets exactly this sort of use case, proving things to a recipient without revealing other things. In this case, you might send a zero-knowledge proof that you have the private key corresponding to a government-signed public key, without revealing either key and, importantly, without communicating with the government or sending correlatable information on each transaction. (If you were ok communicating with the government you could just get it to sign a random public key for each transaction without needing zero-knowledge cryptography). You can do a lot more, for example proving "I am 18+ [attested by gov signature]" without revealing your age, birthday or identity, or "I have security clearance level 2 [attested by gov signature]" without revealing anything else, or "I have a driving license [attested by gov signature] and current paid-up insurance [attested by insurer signature]" etc. The field has advanced technically a lot in the last few years, to the point that those sorts of zero-knowledge proofs are now easy to implement technically and reasonably fast to compute.