Understanding Zero Knowledge Proofs: An Everyday Example

Understanding Zero Knowledge Proofs: An Everyday Example

Zero knowledge proofs are a fascinating concept in the world of cryptography, and although they can be difficult to understand at first, they have everyday applications that we can all relate to.

To put it simply, a zero knowledge proof is a way for one person to prove to another that they know something without revealing the actual information to the receiver. This might sound like a paradox, but it’s actually a clever way of proving something without giving away too much.

Let’s take an example. Imagine you and a friend are playing a game of ‘heads or tails,’ and your friend has just won three times in a row. They might make the claim that they have a trick that gives them an advantage in the game. You might be skeptical and ask them to prove it.

This is where a zero knowledge proof would be useful. Your friend could take a coin and flip it ten times in a row, secretly noting down the results. They could then claim that they know all ten results, but without revealing what they are. To prove this to you, they could ask you to make any sequence of five flips, without telling them what the results are. Your friend could then correctly guess the sequence you made, thus proving that they know all of the results.

This is a simple example, but it shows how a zero knowledge proof can be used to prove a claim without revealing any sensitive information. In this case, your friend could have used their ‘trick’ to make educated guesses about the flips, but they don’t have to reveal the actual method to you.

Another real-life example is in online passwords. When we create a password for a website, we want to make sure that it is secure and cannot be hacked. We might use a zero knowledge proof to confirm that we know our password without actually sending it to the website. This is often done through a process called ‘salted hashing,’ where our password is combined with a random string (the salt) and the resulting combination is encrypted. This encrypted value is then sent to the website, and if it matches what is stored on their server, we are authenticated.

Overall, zero knowledge proofs are a powerful tool in the world of cryptography, with everyday applications that we might not even notice. The next time you hear about a zero knowledge proof, think about how it might be used in your daily life, and be amazed at how clever cryptography can be.