The Power of Zero-Knowledge Proofs: An In-Depth Look at zk-SNARKs

Zcash is one of the most well known cryptocurrency projects that implements zero knowledge proof. But how does this make Zcash unique?
January 5, 2023

What is Zcash?

Zcash is a cryptocurrency focused on privacy that employs a zero-knowledge proof structure known as a zk-SNARK to enable secret transactions.

Zcash was created in 2016 as a fork of the Bitcoin protocol with the inclusion of the zk-SNARK architecture. Zcash, like Bitcoin, is a decentralized, open-source cryptocurrency that records and verifies transactions using a public blockchain.

Unlike Bitcoin, which lets everyone to see the details of every transaction on the blockchain, Zcash allows users to construct shielded transactions, which obscure the sender, receiver, and transaction amount.

Zcash's zk-SNARK structure enables the production of these shielded transactions while retaining the blockchain's integrity. One person (the prover) can prove to another (the verifier) that a statement is true without giving any information about the statement itself in a zk-SNARK.

In the context of Zcash, the prover may demonstrate the validity of a shielded transaction without exposing any transactional information.

The improved privacy and anonymity provided by shielded transactions is one of its primary advantages.

While Bitcoin addresses are not often associated with real-world identities, they are accessible on the blockchain, and third parties may follow and analyze the flow of payments between addresses.

In contrast, shielded transactions in Zcash are completely private, making it much more difficult for third parties to track the movement of funds or link addresses to specific individuals.

Zcash, in addition to its privacy features, offers a number of additional technological qualities that set it apart from other cryptocurrencies.

Zcash, for example, has a proof-of-work algorithm called Equihash that is meant to be resistant to specialized mining gear and to promote decentralized mining.

Zcash also features a slower block time of 2.5 minutes, compared to Bitcoin's 10-minute block time, which contributes to the network's security.

Overall, Zcash is a unique and revolutionary cryptocurrency that has developed a substantial following due to its emphasis on privacy and anonymity.

While it confronts numerous obstacles and concerns, including as the possibility for exploitation by malevolent actors, it remains a prominent participant in the cryptocurrency industry and has the ability to shape the future of online transactions.

Zero-knowledge zk-SNARK, or Succinct Non-Interactive ARgument of Knowledge, is a zero-knowledge proof structure that allows one party (the prover) to prove to another party (the verifier) that a statement is true without giving any information about the statement itself.

In other words, the prover can persuade the verifier that a statement is true without disclosing any knowledge about the statement or requiring any interaction between the prover and the verifier beyond the initial setup.


Zero Knowledge Proof Example

Consider an example to better understand how zk-SNARKs function.

Assume Alice wishes to demonstrate to Bob that she is aware of the secret password to a locked treasure chest without actually disclosing the password to Bob. This is how a zk-SNARK may be used to do this:

1. First, Alice and Bob must go through a one-time setup procedure in which they produce a "public parameters" file that will be used to build and validate zk-SNARKs. This procedure entails the establishment of a trusted environment in which a group of people (dubbed "toxic waste creators") construct a random string of data that is then discarded. This wasted material, known as "toxic waste," is important to the security of the zk-SNARKs since it assures that creating false proofs is computationally impossible.

2. Alice may use the public parameters file to generate a zk-SNARK that confirms she knows the password to the treasure chest after it has been created. She does this by providing the public parameters file and the assertion "I know the password to the treasure chest" to a computer program that creates a proof. This evidence is a short, encrypted file that provides no information about the password but can be validated using the public parameters file.

3. Alice then transmits the proof to Bob, along with the remark "I know the treasure box password." Bob may use the public parameters file to validate the evidence without having to learn the password. If the evidence is correct, Bob is persuaded that Alice knows the password, despite the fact that he has no clue what it is.

The statement "I know the password to the treasure chest" is the "assertion" that Alice is attempting to prove to Bob in this scenario. The computer software generates a zk-SNARK proof, which gives a zero-knowledge proof of the statement without disclosing any information about the password itself.

One of the primary advantages of zk-SNARKs is that they may be used to validate a statement or calculation without disclosing any of the underlying data.

As a result, they may be used in a variety of applications, such as cryptocurrency transactions, voting systems, and anonymous communication networks. Overall, zk-SNARKs are an effective means of ensuring privacy and anonymity in online transactions and interactions.

Finally, zero-knowledge proof structures like as zk-SNARKs provide a strong method for proving the authenticity of a statement or computation without disclosing any of the underlying data.

These proof structures have a wide range of uses, including cryptocurrency transactions, voting systems, and anonymous communication networks.


Conclusion

While zk-SNARKs and other zero-knowledge proof constructs are extremely novel and helpful, it is critical to examine their possible hazards and limits, such as the requirement for a trusted setup and the possibility of malevolent actor misuse.

In general, zero-knowledge proof constructs are a useful tool for providing privacy and anonymity in online transactions and interactions.