Zero Knowledge Proofs

In zero-knowledge proofs, one can prove to know a secret, without revealing absolutely anything about the secret! We give three examples: Where is Waldo?, the color blind problem, and hamiltonian circuits. We show to what degree these are zero-knowledge, and how we can generally prove that a protocol is zero knowledge.

[@moonman239]

So, the basic idea of a zero-knowledge proof is to show that you have information not by revealing the information, but by showing that you know things that would be difficult or impossible to know without having that information?

[@discoETH]

Yes, this is correct.

[@ikcikor3670]

​@@discoETHand also the person you've proven your knowledge to cannot exploit that proof to pretend they know the same information to someone else

[@discoETH]

@@ikcikor3670 This is a good way to put it.

[@umairbutt1355]

​@@discoETH Hmmm. But you may not even HAVE the information right?
An example: A KYC check. You might use a service to do a KYC check, at the end of which the service returns you a hash of the outcome/result - You store the hash. That hash alone can serve as a zero-knowledge proof that you have validated the customer via KYC even though you have no details of the information itself (of course I'm omitting some steps here but the high-level approach holds).
You may then present this hash to regulatory authorities as proof that you indeed did perform a KYC check without storing any details of the KYC process/customer.

[@CarlosSamudra]

The best explained video so far. Thanks.

[@aalampratapbedi7890]

Great video. The video covers all the important points about Zero Knowledge Proof and is easy to understand.

[@doji-san]

When waldo's image was shown through the hole, it also gave information about people near him. So you showed a bit of a proof :D

[@gregorystevens5173]

Zero knowledge proofs do not always imply "zero" knowledge; only that Prover has demonstrated to a degree that Verifier finds sufficient (that Prover can make out his claim). So, in the Waldo example, it's evident that Prover "knows" where Waldo is, and has shown you "without telling you where". Prover did not "tell" us anything. Therefore his claim is true.

[@PurpleHazeVanNederlands]

This example is not a perfect zero-knowledge proof, because the prover does reveal some information about Waldo's location, such as his body position. However, it is a good illustration of the basic concept of a zero-knowledge proof.

[@noracism7382]

​@@PurpleHazeVanNederlandshow would i know that he did not changed the picture with another false image with only copy waldo in it and showed it in the hole.

[@noracism7382]

​@@PurpleHazeVanNederlandsfor sherlock example what if sherlock is a fraud one. And tell every time wrong answer. And if sherlock is truthful , after some iterations watson can himself tell which one is which color that actually defies the intention of zero knowledge proof.

[@ovi4560]

Really good video. Can you make one on zk-SNARKs and in particular the different algorithms for polynomial commitment like FRI, Kate and bulletproofs?

[@TM789]

Super great thank you for this video!

[@InMemoryOfNeo]

It is extending our brain. But we need more. Please make video which explains just algorithm then let us write code. Thanks.

[@jorgin6192]

great video

[@sathyashiva3363]

Nice

[@PhamTony]

Great explanation, I love your voice. Very clear and coherent.

[@diegogimbernat9253]

its AI lol

[@PhamTony]

@@diegogimbernat9253 It's better than most RUclipsrs then in this field.

[@Sontiacsathar]

@@diegogimbernat9253 Is it really? Really good. Specially when you speed it up, it sounds like an actual human

[@astragor2743]

Really cool video, I am writing a scientific work about cryptography and this video was extremely usefull

[@cheesebusiness]

Waldo is behind the train in the bottom right corner

[@jonesbbq307]

Wouldn’t the where’s waldo proof convince a third party?

[@ikcikor3670]

If the 3rd party had access to all the information you do, they'd just be a perfect copy of 2nd party I think, as far as this theory is concerned

[@ikcikor3670]

Having the same prior knowledge and going through the same interactions between themselves and the person who's trying to prove their knowledge

[@ikcikor3670]

Also you can't pretend you have the knowledge to a 3rd party because you don't know how the sheet below the black overlay was moved, so you can use this method to pretend you know something you don't, which in this case is a proof of work that you've look at different places on the board until you've found Waldo

[@paragggoyal1552]

Wow what a zero knowledge proof video, did not reveal anything about zero knowledge proofs.

[@lesterdelacruz5088]

There is no proof here. It’s zero proof.