Author: cookies, venture capital analyst
Compiled by: Felix, PANews
When Ethereum faced network congestion, sky-high fees made the Ethereum network too expensive for some users to afford, causing many users to leave the Ethereum ecosystem. Given Ethereum’s rollup-centric roadmap and Vitalik’s stance that ZK rollups will defeat Optimistic rollups in the future. As an Ethereum sidechain designed to solve scalability issues, Polygon saw the potential of ZK in bringing the next billion users into the blockchain field and invested US$1 billion in building ZK solutions. Regarding Polygon’s layout on ZK, venture capital analyst Cookies interpreted Polygon’s four major ZK solutions.
Polygon Hermez | zkEVM
Hermez is the first decentralized ZK Rollup on the Ethereum mainnet and has been providing payment services since March 2021. Based on the ZK-SNARK architecture, Polygon Hermez aims to solve the scalability problem of the Ethereum blockchain by using zero-knowledge proofs to enable faster and cheaper transactions on the Ethereum network. Since the EVM was not created to generate ZK proofs (ZKP), Polygon Hermez mainly builds zkEVM by recreating all EVM operation codes.
Why zkEVM?
By building zkEVM, Polygon Hermez simulates EVM opcodes to bring the following advantages:
1. Inheriting Ethereum’s strong security
2. Ease of adoption, as the Ethereum developer community can easily migrate their EVM work to zkEVM and use existing tools (good development experience).
Performance
The ZK-SNARK-based architecture is able to provide up to 2,000 TPS and keep costs below 300,000 Gas.
Polygon Zero | SNARK + STARK
Polygon Zero was formerly known as Mir Protocol. When Polygon Zero first developed Plonky2, it took 2 minutes to generate a recursive proof. Now Plonky2 can generate a recursive proof on a laptop in just 170 milliseconds.
Polygon Zero ultimately aims to build the most scalable zkEVM powered by Plonky2. Plonky2 is a recursive SNARK that is 100x faster than any other ZK scaling solution on Ethereum. This is achieved by combining the advantages of STARKs (fast proofs and no trusted setup) with the advantages of SNARKs (recursive, low verification cost).
EVM Compatibility
Plonky2 is compatible with native Ethereum, supports Solidity code, and converts it into ZK bytecode, so that Polygon Zero can take advantage of the existing Ethereum dApp ecosystem.
Polygon Miden | STARK
STARK-based rollup has the following features:
Transparent and scalable: no trusted setup/preprocessing required Lean cryptography: future quantum computer attacks are impossible High performance: leading proof generation and verification times
Polygon Miden is centered around the Miden VM (virtual machine) and supports arbitrary programs. It is more developer-friendly by hiding all the cryptographic complexity of ZKP and following the architectural patterns familiar to developers (stack machines, read-write memory, etc.).
Safety
One of the main features of Polygon Miden is security. The protocol removes some unsafe functions (available on the EVM), which makes it easier to perform static analysis of smart contracts and prevent certain bugs at the virtual machine (VM) level.
EVM Compatibility
Miden is compatible with Ethereum at the Solidity level. Developers can deploy most Solidity smart contracts on Miden without modification. Another novelty is the compatibility with other languages such as Move and Sway.
Performance
At launch, the TPS will be between 1000 and 2000. Once sharding is deployed on Ethereum, the TPS will reach about 20,000 TPS.
Polygon Nightfall| Optimistic + ZK
In contrast to the aforementioned ZK solutions, Nightfall focuses on private transfers and payments, supporting ERC20, ERC721, and ERC1155 tokens.
Any data that does not need to be stored on the smart contract is stored off-chain, optimizing the smart contract. The team is working on an instant withdrawal mechanism so that users can bypass the 1-week deadline for submitting fraud proofs. The protocol is significantly slower, reaching a maximum of 105 TPS. However, it is estimated that the gas fee for transfers can be reduced by up to 86%, stabilizing at about 9,000 gas.
Compare
The following figure is the author's summary of the four solutions:
in conclusion
Clearly, Polygon is investing a lot of time and money in spearheading the development of ZK scaling solutions. We will have to wait and see how the mainnet performs and how it works with other ZK protocols.
Related reading: Learn about 5 expansion solutions under the Polygon ecosystem in one article