Original Author: DeWei @DAOrayaki.org

Original title: Where Polygon zkEVM Fits in the Market

Polygon zkEVM Built by Polygon, it provides projects with the benefits of ZK-proof scalability and compatibility with the Ethereum Virtual Machine (EVM). EVM compatibility means developers can easily port Ethereum smart contracts with minimal code changes. ZK rollups are a scaling solution that increases throughput by moving computation and state storage off-chain, while maintaining high security guarantees using zero-knowledge cryptography.

However, the purpose of this article is to highlight where Polygon zkEVM fits within a broader market context - for a full understanding of Polygon zkEVM, check out the project documentation.

Technology Stack Overview

Let's first look at the framework of the blockchain stack. Blockchain consists of four layers. We will use Volt Capital's definitions for each layer.

Execution: Transactions and state changes are initially handled here. Users also typically interact with the blockchain through this layer, signing transactions, deploying smart contracts, and transferring assets.

Settlement: The settlement layer is where rollup execution is verified and disputes are resolved. This layer does not exist in Monolithic Chain and is an optional part of the modular stack. In analogy with the US court system, the settlement layer is regarded as the highest court in the United States, providing final arbitration for disputes.

Consensus: The consensus layer of the blockchain provides ordering and finality through a network of full nodes, downloading and executing the contents of blocks, and reaching consensus on the validity of state transitions.

Data Availability: Data required to verify that state transitions are valid should be published and stored at this layer. This should be easy to verify in the event of an attack where malicious block producers withhold transaction data. The data availability layer is the main bottleneck of the blockchain scalability trilemma, and we will explore why later.

We will also use Celestia's definition of a modular blockchain.

A blockchain that focuses on only a few features rather than all of them. The key functions are:

• implement

• consensus

• consensus

• data availability

Modular blockchains are arranged as modular stacks, with each blockchain in the stack called a "layer". Since modular blockchains provide only a subset of key functionalities, this allows them to be purpose-built for the functionality they provide.

For example, Celestia is a consensus and data availability layer, as it only provides ordering of transactions (consensus) and verification of their data availability.

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Scope of application of Polygon zkEVM

In the blockchain stack, the Polygon zkEVM is considered a modular blockchain, more precisely, an execution layer. It serves as a platform for users to build applications and direct transactions, while outsourcing settlement, consensus, and data availability to Ethereum.

Let's take a look at how the Polygon zkEVM interacts with other layers.

As mentioned above, the execution layer is where users conduct transactions. When a user signs a transaction, the transaction is queued and processed - the same way as on Ethereum.

once a"batch"The transaction is processed, and three important things happen:

• Generate ZK proof

• ZK proofs are published on Ethereum

• Transaction data is published on Ethereum

Polygon zkEVM has a system for generating ZK proofs, which consists of two roles: a Sequencer and an Aggregator. Both roles are permissionless, so anyone can participate.

ZK proofs are published on Ethereum which acts as a settlement layer. Ethereum smart contracts verify ZK proofs, effectively checking the work of Polygon zkEVM nodes and ensuring that all calculations are done correctly.

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• Security Spectrum: How much security does Polygon zkEVM inherit from Ethereum?

To measure this, we'll look at the graph below, which puts the Polygon zkEVM on the safe side. The solution on the left is not protected by Ethereum, and the solution on the right is fully protected by Ethereum.

Polygon zkEVM (formerly Polygon Hermez) is on the far right - co-located with other ZK rollups and Ethereum data shards.

As you may already know, Polygon has made a major strategic bet and financial commitment to ZK solutions - allocating $1 billion in funding to ZK R&D. As a result, there are now four ZK rollups in the Polygon suite: zkEVM, Miden, Nightfall, and Zero.

Each ZK rollup has a different design (e.g. Nightfall is a hybrid optimistic ZK rollup), but they all fundamentally use the same ZK primitives and fully inherit the security of Ethereum.

Data shards are also fully protected by Ethereum because (once implemented) they will be baked into the core Ethereum protocol.

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• economic security

We have always said that rollup inherits the security of Ethereum. You may already have an idea of ​​Ethereum’s economic security, but let’s put it in context and evaluate Proof-of-Stake (PoS) Ethereum.

Currently, there are about 13.3 million ETH pledged on the Beacon chain, totaling about $22 billion at current token prices. Under the 2/3 honest majority assumption, it would take about $15 billion to compromise the network. This is by far the best in the crypto industry.

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• protocol stability

Although ZK cryptography has been around for over 30 years, practical applications like ZK rollup are still in their infancy.

risk factors

• risk factors

Technically speaking, Polygon zkEVM may not start as a rollup, but as a validium or volition. In the docs, this is referred to as a "hybrid mode of on-chain data availability".

This means Polygon zkEVM will not be fully secured by Ethereum. When validium and volition publish transaction data off-chain, they inherit additional trust assumptions. For example, if Polygon zkEVM were to issue ZK proofs on Ethereum (using them for settlement) and data on Celestia (using them for data availability), it would rely on an honest majority of both Ethereum and Celestia validators. If there are failure modes on either chain, the entire system is at risk.

competitive landscape

competitive landscape

performance

• performance

• safety

• safety

• developer experience

Performance and cost are pretty straightforward. Developers want their apps to be fast and cheap in order to provide users with a better experience.

There may be an argument here: Polygon zkEVM competes with EVM-compatible L1 (such as Avalanche) in terms of performance and cost. In the short term, this is likely to be true. However, we won't take the time to do this comparison, because any successful L1 that is still optimized for high performance and low cost would require a significant increase in expense or take unsustainable risks.

The real competitors of Polygon zkEVM are other EVM-compatible rollups - ZK (eg Scroll) and optimism (eg Optimism). There are many articles comparing the two rollup types, so we won't go into depth, but a simple approach is to consider that ZK rollup has higher performance (due to faster finality, which we will discuss shortly), and optimistic rollup has Lower cost (due to ZK computational intensity).

Note: It is unclear how Polygon zkEVM will compare to other ZK rollups in terms of performance and cost.

In terms of security, Polygon zkEVM is much better than L1, and basically the same as other rollups (ZK and optimistic similar).

Finally there is the developer experience, which we split into finality and EVM compatibility.

Finality is "the time at which a transaction is considered final from the perspective of the base layer contract." ZK rollups have faster native finality than optimistic rollups. This is because optimistic rollup designs rely on "observers", nodes that monitor the chain for fraud. Because observers need enough time to detect fraud and publish proofs, finality is typically delayed by a week (typically minutes for ZK rollups)—meaning longer wait times and a degraded user experience. Optimistic rollups have some workarounds for faster finalization of liquid tokens, which Alex mentions in the above post, but in general ZK rollups have an advantage.

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So, what is the state of the Polygon zkEVM today?

From a technical point of view, Polygon zkEVM"Has passed 60% of the Ethereum test vector suite used to establish EVM equivalence. Polygon zkEVM's zkProver is now able to process 500,000 GAS on a single CPU in 5 minutes". Impressive stuff - considering ZK proof generation is a computationally intensive task.

From an entry-to-market perspective, this is a solid achievement. According to the timeline outlined by Mihailo in a recent Bankless interview, the testnet should be readily available now, while the mainnet should still be a few months away.

It must be acknowledged how much the ZK team has achieved. ZK rollups use state-of-the-art cryptography (moon math as some say) and go from theory to practice years in advance. Building an EVM-compatible ZK rollup is more challenging, and the fact that multiple zkEVM teams own mainnet is mind-boggling.

Which zkEVM teams will win remains to be seen, but one thing is for sure - the fact that we are at the starting line is a huge win for web3.