Amazing article. Will save to explain ZKP to others.<p>One tiny correction<p>random.randrange(100) gives 300 possible commitments(3 colors for hundred nonces) After seeing a couple of revealed edges, the verifier can figure out the palette and brute-force all 300 combinations, effectively opening every commitment.<p>It can be mitigated if we use 128 bits of randomness, e.g. secrets.token_bytes(16).<p>Also I would use sha256 instead of hash. Python hash is not considered secure as it does not have proper collision resistance.
I don't think ZKPs / programmable cryptography are useless like some of the other commenters. But I do remember being surprised, based on the way that people talk about building on top of it, to learn that the performance is so bad (except on dedicated servers) that it's basically a theoretical technology until that's fixed. Has this changed recently? Not a rhetorical question.
Zcash make a significant contro to ZKPs though, what would be the state without their tec?<p>Did their advancements have any other implications besides cryptocurrency?
Not one mention that ZKP depends on servers trusting clients.<p>The single reason ZKP is not viable for most security is that it relies on you trusting the client to send you true information <i>about</i> data.<p>With conventional security the user sends their inputs and the server validates it.<p>Something I notice that is almost never mentioned when people bring up ZKP - it is pretty much <i>only</i> for peer-to-peer when there is no authoritative server. Or when that server trusts the “nodes” (clients).
<p><pre><code> > relies on you trusting the client to send you true information about data
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this is false. the client is constrained to send you true information or else the verifiers will know to reject it.<p>ZKP's are not magic, you need a cryptographic operation on which to operate the ZKP. this way you can conceal the input while still proving something about it. this works because the ZKP follows the trace of execution through the cryptographic primitive which proves it was executed properly and then the output was validated by some public measure.<p>conversely, if ZKP's ever get fast enough to be useful for this you can prove a public input (ex. source code) was compiled properly into a public output (ex. binary). for obvious reasons doing this only makes sense when it's efficient otherwise you can just execute it yourself.
What is your envisaged application? ZKPs give you integrity guarantees which prevent malicious behaviour.
ZKP is 100% bullshit.<p>It’s a new word invented by people who don’t know hashing and databases already exist.
PAKE has been using ZKPs for a decade. Here. Read this : <a href="https://en.wikipedia.org/wiki/Password_Authenticated_Key_Exchange_by_Juggling" rel="nofollow">https://en.wikipedia.org/wiki/Password_Authenticated_Key_Exc...</a><p>Funny that not only are you ignorant you are violently confident in your ignorance. I suffer from this sometimes too so I get it. Get some help.
> Alice sends out<p>It relies on trusting that Alice’s request is valid. If Alice sends another proof, she will have a different balance. Alice decides what to send. The server blindly accepts it.<p>You actually don’t want that for a lot of security and that’s why nobody uses ZKP for passwords or really anywhere outside theory - dumb theory that doesn’t understand basic web dev. We already have hashing and databases. There is a narrow use case for trusting clients - like receiving updates from intranet or p2p devices - maybe you use ZKP to omit unnecessary pii. But that’s it. It’s not what you think it is.
> Alice sends out<p>Alice can send anything in any cryptographic scheme involving two parties, the only real safety in any of it is "are the odds of an accepted different value low enough to be impractical for an attacker". Does that apply here too?
Please explain how Alice’s request can ever be not valid. It’s literally a pre authenticated exchange.<p>Also nice sock puppet.
A great way to announce that you don't understand ZKP
It has a use case in peer-to-peer or anywhere that you want the server to trust the connections.<p>Sometimes you want clients to be authoritative (although rare).
Yes, they just hand out Turing Awards for bullshit.