Zero Knowledge Proofs (For Beginners)

In the time it takes you to read this article, one ‘Zksync, Zksync era, or Zero Knowledge protocol’ has been mentioned on the internet.

I kid you not, dear reader, that’s how popular Zkproof is spreading in the Web3 space. But as usual, I take time out of my marketing schedule to share value with you.

This article would be your foundation for understanding Zero-knowledge proofs and their application for future Web3 opportunities.

What Do Zero-Knowledge Proofs Mean?

Zero Knowledge proofs(ZKPs) are a secret writing method used to prove the truth of something without revealing the entire process of achieving it.

The party who is trying to prove something is called the prover, while the party who is trying to verify the truth of something is called the verifier.

ZKPs try to satisfy 3 principles:

• Statistical Soundness: This means that If the statement being proved is false, no dishonest prover can convince an honest verifier.
• Completeness: This means if the statement being proved is true, an honest prover will be able to convince an honest verifier.
• Zero Knowledge: The verifier learns nothing about the prover’s secret information beyond the fact that the statement is true.

How Many Diverse Zero Knowledge Proofs Exist?

Zero-knowledge proofs (ZKPs) come in two main categories: interactive and non-interactive.

1. Interactive ZKPs(IZKPs): In IZKPs, the prover and verifier engage in a series of rounds until the verifier is convinced.

The prover wants to prove knowledge of a secret without revealing it, while the verifier wants to be convinced of the prover’s knowledge without learning the secret.

Zcash, a privacy-focused cryptocurrency, uses IZKPs to allow users to make anonymous transactions.

2. Non-Interactive ZKPs (NIZKPs): Contrary to IZKPs, the proof is delivered offline without direct communication to the verifier in NIZKPs.

The prover generates a proof that encapsulates all the necessary information, and the verifier can independently verify the proof without further interaction.

NIZKPs offer greater convenience and efficiency, as they don’t require real-time communication between the parties.

Decentralized storage network, Filecoin, uses NIZKPs to prove that users have stored data without revealing the data itself.

Now, within these two broad categories, there exist various types of ZKPs, each with specific properties and applications.

Some common examples include:

• zkSNARKs (Zero-Knowledge Succinct Non-Interactive Argument of Knowledge): It’s not a snack😅! These are a type of NIZKPs that are particularly efficient and compact, making them suitable for use in blockchain and cryptocurrency applications e.g. Aztec Protocol, a privacy layer for Ethereum uses zkSNARKs to enable confidential transactions.
• zkSTARKs (Zero-Knowledge Scalable Transparent Argument of Knowledge): If you thought about Tony Stark, well, right back at you😅! These are another type of NIZKPs that offer enhanced scalability and transparency compared to zkSNARKs. Blockchain scaling solution, StarkWare, uses zkSTARKs to improve transaction speed and privacy.
• Proofs of Shuffle and Range: These are a kind of zero-knowledge proof that can be used to demonstrate that a set of data has been shuffled or that a specific value falls within a certain range without revealing the actual data or value.
• Sigma Protocols: These are a foundational type of ZKP that forms the basis for many other ZKP constructions. An example is Zero-knowledge identification schemes, which allow users to prove their identity without revealing personal information.
• Bulletproofs: These are a type of range proof that offers improved efficiency and privacy compared to traditional range proofs. Monero (a privacy-oriented cryptocurrency) uses Bulletproofs to improve transaction efficiency and privacy.

The choice of which Zero Knowledge Proofs to use depends on the specific requirements of the application, such as the level of privacy, computational efficiency, and proof size.

Like any other thing, technology has both advantages and disadvantages.

To quote the controversial American author of The Da Vinci Code,

“Technology is a double-edged sword. It can be used for good or evil. It can help us or hurt us. It can bring us together or drive us apart. It can make us smarter or make us lazier.” — Dan Brown.

Let’s review the pros and cons of ZKPs

Pros

1. Simplicity: ZKP does not require a complex encryption method which is great. Not everything about the blockchain must be rocket science if we’re going to drive adoption.
2. Security & Privacy: It strengthens the security of information by replacing ineffective authentication methods. Also, it increases the privacy of users by avoiding the reveal of personal information.

Cons

1. Large Amount of Computing Power: Generating and verifying ZKPs can be computationally intensive, requiring efficient implementations and optimizations.
2. Implementation complexity: ZKPs can be difficult to implement correctly. If a ZKP is implemented incorrectly, it could be vulnerable to attack.

Where Can You Apply Zero-Knowledge Proofs?

Like any other tool, zero-knowledge proofs (ZKPs) have a wide range of applications. Here are a few practical examples of how they are being used in various applications:

1. Privacy-Preserving Authentication: ZKPs can be used to authenticate users without requiring them to reveal their passwords or other sensitive information. For instance, a user could prove they know the correct password without actually disclosing it to the system.
2. Anonymous Transactions: ZKPs can enable anonymous transactions on blockchain networks, allowing users to transfer funds without revealing their identities or transaction details. This can enhance privacy and protect users from potential surveillance or tracking.
3. Verifiable Credentials: ZKPs can be used to issue and verify credentials, such as educational certificates or professional licenses, without revealing the underlying personal information. This allows individuals to prove their qualifications without compromising their privacy.
4. Secure Voting Systems: ZKPs can be implemented in voting systems to ensure the integrity and privacy of votes. Voters can prove they are eligible to vote and have cast their ballot without revealing their identity or their vote choice.
5. Supply Chain Transparency: ZKPs can be used to provide verifiable proof of product authenticity and supply chain traceability without disclosing sensitive business information. This can enhance consumer trust and combat counterfeit products.
6. Privacy-Enhanced Data Sharing: ZKPs can facilitate secure data sharing between parties without revealing the underlying data itself. This allows organizations to collaborate on data-driven projects while protecting sensitive information.
7. Regulatory Compliance: ZKPs can be used to demonstrate compliance with regulations without revealing confidential business data. For example, a company could prove it has implemented certain security measures without disclosing the details of those measures.

Disclaimer: This article was written to provide guidance and understanding. It is not an exhaustive article and should not be taken as financial advice. Obiex will not be held liable for your investment decisions.