Protecting privacy is of utmost importance in the blockchain industry. Zero-knowledge proof systems help to achieve this goal. Learn more about them in this guide!
What Is Zero-Knowledge Proof?
Zero-knowledge proof, aka a ZK protocol, is a verification method through which the prover can demonstrate to the verifier that they possess certain information, such as a solution to a math equation, without revealing the information itself. Such systems are often used by modern cryptographers to ensure advanced privacy and security.
What You Need To Know About Zero-Knowledge Proof
The zero-knowledge proof concept was introduced in a 1985 MIT paper, published by Silvio Micali and Shafi Goldwasser.
The document described the possibility of proving some properties of a number without disclosing neither itself nor any additional information related to it. This paper also revealed the finding that interactions between a prover and a verifier can reduce the amount of information required to prove a given theorem.
The zero-knowledge proof system has three core components:
- Completeness. The prover must be able to show the possession of relevant information with a high degree of probable accuracy.
- Soundness. This means that the verifier should have the ability to reliably determine whether or not the prover indeed has the information in question.
- Zero proof. As you already know from the zero-knowledge proof definition, the consensus must be achieved without the actual piece of information being shared between the prover and the verifier.
There are plenty of use cases of zero-knowledge proof protocols. For instance, authentication systems utilize them to verify credentials or identities without directly disclosing them, such as when a user proves they have a password to a computer system without revealing it.
Zero-knowledge proofs have also proven to be useful across the crypto space. Cryptocurrencies like Zcash use a proof called the zk-SNARK (zero-knowledge Succinct Non-interactive Argument of Knowledge) as a means to ensure advanced privacy for blockchain transactions.
Notably, Ethereum has also been implementing zk-SNARK proofs since its 2017 Byzantium update.
