What Are Zero Knowledge Proofs?

What Are Zero Knowledge Proofs?


Hey, there guys. Glad to see you here for
another PIVX Class. Today we’re going to cover
Zero-Knowledge Proofs. Now, you may not have even heard of
these before but that’s all right. I think you’ll find this video
pretty cool despite that. They are an integral part
of many privacy-focused cryptocurrency including those
that use the Zerocoin Protocol. But the concept around them
has existed since the 80s and was not originally
intended for cryptocurrencies. They can be used in a lot of
security applications as well as
other fields given the need. If you’re keen on figuring how
exactly these work we should be
able to get you there today. So without further
ado let’s begin. To begin with, we should answer
what is a Zero Knowledge Proof? It essentially is proving that you
know something without revealing
the secrets of how you know. This can be either incredibly
difficult or incredibly easy
depending what you want to prove. A true Zero-Knowledge Proof
has to meet three criteria: One, completeness. The test can fully convince
the other person that you know
what you say you know. Two, soundness. The test can only convince the other
person of the truth and not a lie. And three, Zero-Knowledgeness. The test can reveal nothing
else to the other person. To demonstrate this I’m going
to use a variation of an analogy that is quite popular
for explaining this topic. Let’s say I am completely blind. You hand me these two balls. You know that they have
a different pattern on them but as far as I can tell these
balls are identical because
I can only feel them. You tell me these two balls
are different but I don’t
believe you because you are frequently lying to me
about all sorts of tall tales. You get a little offended so you
decide to mess with me a bit. You decide you’ll prove to me
that the balls are different but you don’t want to
reveal which one is which. This means you now have the
challenge of proving that the balls are different without telling
me anything more about them. You tell me to hide the balls
and reveal one of them. I do so. Now you tell me to hide it again
then reveal one again
but choose myself which one. I decide to switch the ball. You tell me that I switched. If the balls were identical you would
not have been able to guess that. I scoff at you, phuh, lucky guess. So you tell me to do it again. I hide the ball and this
time pull out the same ball. You tell me I didn’t switch. I used the same one. I get mad and exclaim you are
lucky and make you
do it a hundred more times. After you guess it right
one hundred times I give up
and tell you that you have won. There’s no way you could be
so lucky as to guess it right
one hundred times in a row. Obviously, the test has a flaw
in the fact that I’m blind. You could put a mirror or something
behind me and I wouldn’t even know. In this case, you could modify
the test so that I could pick anyone I wanted to make sure
you weren’t cheating me. They would only be allowed
to stand in the room and tell me if you cheated and not any
information about the balls. This would prevent any possibility
of you cheating unless you have
super powers like x-ray vision. But unfortunately, the Avengers
only exist in fiction. So that experiment
covered completeness. Because after one hundred
trials I never fooled you once. The balls must be different. Our small modification of adding
a third person has also made our
test fulfill the need of soundness. There’s no way you could cheat me
with someone else in the room
guarding against it. And Zero-Knowledgeness? Well, if you walk away
with these balls I will never know which
one is which, will I? And that means I never found out
any additional information. With that, all three requirements
are met and we have a Zero-Knowledge Proof that
those balls were indeed different. This concept can be
applied to cryptocurrency through the Zerocoin Protocol
and other similar concepts. In the case of PIVX,
we touched on the subject of using Zerocoin in the
Zerocoin Protocol video. I’ll throw the card up
on the screen now
so you can see that example. That example used the
Zero-Knowledge Proofs to function. You can prove that you own currency
without needing to actually reveal which denominations are yours
through these methods. This allows you to spend money
without attaching any of that
money’s history to yourself. That video above has an analogy
that can kind of explain
what I’m talking about here. But it’s pretty crazy that you
can use Zero-Knowledge Proofs to add additional privacy
to your everyday transactions. I will make a video in the
future explaining the usage of Zero-Knowledge Proofs
in Zerocoin but for now, we’ll avoid information
overload because that can
get a little bit more technical. You can now tell people you know
what a Zero-Knowledge Proof is. It’s just a method of proving
you know a secret without
revealing that secret. I hope you enjoyed this class. If you have any questions
or you’d like to suggest the next video please
comment down below. And if you found this video
helpful please throw us
a like and share the video. It helps the channel out a lot
and puts a smile on my face. Thank you for tuning in guys,
I love having you, and I will see you in
the next PIVX Class.

You May Also Like

About the Author: Maximilian Kuhn

11 Comments

  1. It's Rick Astley everyone ..

    Never gonna give you up

    Never gonna let you down

    Never gonna run around and desert you

    Never gonna make you cry

    Never gonna say goodbye

Leave a Reply

Your email address will not be published. Required fields are marked *