Analysis: Why Zero-Knowledge Proofs Will Penetrate Every Corner of Web3？

Jul 01, 2024

Author: Hu Feitong

Original link: https://mp.weixin.qq.com/s/h4W_ElxEWIYpt0NLp2SAfA

First, let’s talk about what Web3 is. Simply put, Web3 is the decentralized internet. It’s meaningless to discuss Web3 without decentralization.

The Premise of the Impossible Triangle

When it comes to decentralization, blockchain is indispensable. And when it comes to blockchain, one cannot escape the blockchain trilemma: decentralization, scalability, and security cannot all be achieved simultaneously.

But this has a premise, which is within certain technical conditions. Under these conditions, improving one or two aspects inevitably sacrifices the others. For example, many current projects claim to achieve TPS (transactions per second) in the thousands or even tens of thousands, reaching up to hundreds of thousands. This is achieved by sacrificing security and decentralization. Therefore, these projects do not have a strong security foundation. In more extreme cases, they are essentially internet projects disguised as Web3, selling dog meat under the guise of sheep.

What if there is technological progress?

However, achieving all three is not impossible and requires technological advancements. When breakthroughs in technology occur, overall improvements become possible. For example, if computing power and network speed increase, TPS can be improved without sacrificing security and decentralization.

Technological progress can lead to unilateral or comprehensive breakthroughs. For instance, the development of storage proofs has enabled PoC (Proof of Capacity) consensus to achieve security similar to PoW (Proof of Work) consensus. Thus, blockchain may not need to rely on energy-intensive methods to provide decentralized foundational trust. The development and widespread application of Byzantine consensus allow for PoS (Proof of Stake) to provide a downgraded security foundation for scenarios with lower security requirements. Advances in cryptography enhance transaction security, balancing security and usability. The development of zero-knowledge proofs may provide comprehensive breakthroughs, potentially supporting decentralization, security, and scalability all at once.

What is Zero-Knowledge Proof?

Simply put, zero-knowledge proof is a cryptographic method that allows one party (the prover) to prove to another party (the verifier) that certain information is true without providing any additional information.

This explanation might seem too abstract, so let’s break it down into two main aspects:

1) Proof: This means using a proof string (a fixed-length pseudo-random number) to prove something. This could be a piece of stored data, a completed computation, etc.

2) Zero Knowledge: This means that while proving the related information, no actual information is leaked. It proves that a computation has been done without revealing the specifics of the computation or the input data.

Still too abstract? Let’s make it more concrete: For example, you store a piece of data on Baidu Cloud. How do you know Baidu Cloud hasn’t lost or tampered with your data? You don’t, unless you download it and compare it, which is cumbersome. So, you simply choose to trust it, and if something goes wrong, you address it afterwards.

Another example, you rent a virtual machine on Alibaba Cloud to run a program. How do you know the result of this program execution is correct? You assume it is correct. You think, why would Alibaba Cloud bother to deceive you? So, you trust it. But there’s no guarantee, no proof.

However, if there were technological advancements that enabled Baidu Cloud or Alibaba Cloud computing platforms to provide you with a mathematically rigorous proof after each storage or computation, a proof that you can easily verify, then you wouldn’t have to simply trust them — you could choose to verify. This is especially important in decentralized networks. Remember: Don’t Trust, Verify!

If these proofs are publicly verifiable, meaning anyone, including you, can verify them without exposing any private information, then it would be perfect. This is what zero-knowledge proof is all about.

Why Zero-Knowledge Proofs Will Be Ubiquitous?

First, let’s understand why Baidu Cloud or Alibaba Cloud doesn’t provide such proofs. The reason is simple: zero-knowledge proof is a new technology that, despite its rapid development, is still immature. Currently, the cost of using it is very high. In simple terms, generating proofs is significantly more expensive than redoing the computation itself by several orders of magnitude, making it impractical.

However, in decentralized networks, the situation is somewhat different. Firstly, decentralized networks are inherently expensive. For example, the computation on Ethereum — just look at the Gas fees. These high costs are due to the need for every node to repeat the same computation, making the cost thousands of times higher than centralized computation. If we could compute off-chain and directly submit proofs on-chain, then the computation only needs to be done once while still ensuring security. This is the theoretical foundation of zkRollup. Most zkRollup computations are centralized, but their computations are submitted to a decentralized network for verification, leveraging the security of Layer 1. The network is expanded through this layering. This means the network expands without weakening security, and the decentralized foundation remains intact.

Not only can zkRollup use zero-knowledge proofs to leverage the security foundation of Ethereum Layer 1, but we can also directly innovate Layer 1 itself. With zero-knowledge proofs, we might not need to do repetitive computations on Layer 1; only decentralized verification is needed. This leads to the emergence of zkVM, such as Aleo, which is a new blockchain network that performs off-chain computation and on-chain verification using zero-knowledge proofs. Its security is ensured by a large number of verification nodes.

So, if zkRollup can use zero-knowledge proofs to scale Layer 1, can other applications do the same? Absolutely. This is why many applications now run a Layer 2, directly submitting proofs to the main chain to leverage its security and achieve decentralized trust. This way, numerous Web2 applications can be integrated into a secure blockchain network and can directly interact with BTC, Ethereum, or Filecoin.

With zero-knowledge proofs as a foundation, there’s an opportunity for Web2 applications to migrate to Web3. A possible Web3 architecture could be:

1. Some sufficiently decentralized blockchain networks that use consensus mechanisms like PoW or PoC, or well-established PoS networks, establish decentralized network trust and serve as the security foundation for Web3.

2. Zero-knowledge proof service layers that provide zero-knowledge proof services, linking applications with secure blockchain networks.

3. Decentralized storage networks that build the DA layer, using zero-knowledge proof technology to ensure privacy and data security.

4. Various applications that use centralized computation, construct proofs through the zero-knowledge proof service layer, and use blockchain networks for verification to ensure correctness and completeness. Data storage utilizes decentralized storage networks, also ensuring correctness and completeness through zero-knowledge proofs.

How Long Will It Take?

Some might ask, the current Web3 applications don’t seem like this, right? Indeed, they are not. Web3 is still in its infancy.

Currently, Web3, from an application layer perspective, either places contracts on Layer 1, relying on repetitive computation to provide security, or merely puts tokens in contracts to disguise them as Web3 (without decentralized security guarantees). A promising trend is that many Web3 projects can run within Rollups, using OP or ZK methods to leverage Layer 1 for security. However, we can see that Web3 is still very niche, mainly focused on finance (DeFi). GameFi and SocialFi, which have been talked about for years, are still in the experimental stage.

Imagine, without decentralized storage (a sufficiently decentralized DA network), data cannot be decentralized, and applications with large data interactions cannot achieve Web3. Moreover, zero-knowledge proof technology has only theoretically proven its feasibility; its efficiency and cost-effectiveness still need significant improvements through engineering and methodological advancements. These two areas are crucial for the future development of Web3. When substantial breakthroughs are achieved in these areas, the era of a decentralized internet will have arrived, and so will the Web3 era. At that point, even Baidu Cloud and Alibaba Cloud will need to prove their services through a decentralized trust network. Otherwise, new application paradigms will naturally emerge to meet this demand.

How long will it take exactly? It’s hard to say. But the trend is clear. Do not have overly high short-term expectations, and do not underestimate the power of long-term gradual development. The singularity might just be in the next cycle.

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