<h2 class="wp-block-heading">What is happening?</h2>Polygon will be launching its zkEVM Mainnet Beta on March 27th, 2023. This is a significant milestone in the roadmap to scale Ethereum and unlock the full potential of Web3, paving the way for mass adoption.<h2 class="wp-block-heading">Why is this significant?</h2>If you’ve ever used Ethereum Mainnet during periods of heavy network activity, you’re probably familiar with the not-so-smooth (and sometimes costly) experience it can provide for everyday users. Fortunately, Layer 2 networks like Polygon have emerged with solutions to help mitigate some of these issues. Among the most promising scaling solutions are ‘Zero-Knowledge Rollups’ (zk-Rollups). These offer a viable path to scale Ethereum in a cost-effective and efficient manner.&nbsp;A zk-Rollup is a layer 2 construction on top of Ethereum that solves its scalability through mass transfer processing rolled into a single transaction. The technology is used to present and publicly record the validity and correctness of the rolled transfers processed on the Ethereum blockchain. Storing only the proof and compressed data of a batch of transfers results in a significant increase in the network’s efficiency and throughput.<img src="https://lh5.googleusercontent.com/3cusXNI7bsaYKoLPbVemu6HSd2TAK6J_IS2Ll4tmbhsbX9tUBMqkl2yv-s04U60fdWM4W6dSQWcHH3hBkf3ymkLU7xn5bNeotLeoBzZi1YNn9i-WbSmGlhYUTn-I2KmDTgC8BZR5TtAlM8jUNCEBBlo" decoding="async" loading="lazy" width="624" height="359">Now that may seem like a mouthful, but all you need to know is that ZK proofs reduce transaction costs and massively increase throughput, all while inheriting near proximal security to Ethereum’s L1. Sounds great doesn’t it, let’s dive into the details!<h2 class="wp-block-heading">What are the main features of the Polygon zkEVM?</h2>Polygon zkEVM is a Layer Two (L2) scaling solution for Ethereum that leverages the scaling power of zero-knowledge (ZK) proofs while maintaining Ethereum-compatibility. Developers and users can use the same code, tooling, apps, etc that they use on Ethereum, but with much higher throughput and lower fees. Enabling them to copy and post their code, and enjoy the benefits of ZK technology. We can describe the core features of the upgrade as follows:<img src="https://lh5.googleusercontent.com/4mDp6fmXjDb1aeX2x8Ea-bDYvkWsp6-6sY8wyS00aAbrNeFdXc1SIRwUL2D6WRnoofW9VpfGdE64-FKALbKqu_rnXxt8wRamQyrsSWojCYTa7KRbqgDo6YOxRuwNc0n2BXw_m2hbFzOEhGWHHOvRPcI" decoding="async" loading="lazy" width="624" height="359"><h2 class="wp-block-heading">What are the benefits of Polygon zkEVM?</h2>True EVM-equivalence allows scaling Ethereum without relying on half-measures. To scale Ethereum effectively, it is necessary to preserve the existing Ethereum ecosystem, including its code, tooling, and infrastructure. This approach ensures that everything functions properly, which is precisely what Polygon zkEVM aims to achieve. In addition, much-anticipated transaction cost reductions are included in the upgrade:<ul><li>Cost for generating a proof for a large batch of transactions down to about $0.06</li><li>Less than $0.001 for a simple transfer</li></ul>The Polygon foundation has highlighted&nbsp; four key benefits of the upgrade for Ethereum ecosystem developers and users:Secure scalabilityzk-Rollups offer stronger security assurances when compared to alternative scaling solutions, as they employ validity proofs to verify the accuracy of off-chain computations. This approach enables smart contract transactions on Layer 2 to be verified on L1 (Ethereum) without the need for nodes to re-execute operations, resulting in significant time and resource savings. As a result, Ethereum’s processing speed can be significantly increased without compromising security.Cheaper costszk-Rollups can afford to post minimal data to Ethereum because validity proofs already guarantee the trustworthiness of state transitions.Faster finality and capital efficiencyThe zkEVM typically confirms transactions immediately after they are posted to Ethereum. Since each transaction batch comes with a verifiable proof of validity, state updates can be rapidly applied to the main Ethereum chain.Network effectsThe primary rationale for developing EVM-compatible zkVMs is to capitalize on the network effects of Ethereum. As the largest smart contract platform in the world, Ethereum has a vast ecosystem that offers significant value to both developers and projects.<h2 class="wp-block-heading">Polygon zkEVM uses Proof-of-Efficiency, not Proof-of-Stake</h2>David Schwartz and Jordi Baylina from Polygon Hermez (Scaling Solution) outlined a <a target="_blank" rel="noopener noreferrer" href="https://ethresear.ch/t/proof-of-efficiency-a-new-consensus-mechanism-for-zk-rollups/11988">new consensus model</a> to overcome <a target="_blank" rel="noopener noreferrer" href="https://ethresear.ch/t/against-proof-of-stake-for-zk-op-rollup-leader-election/7698">unique challenges</a> that Layer 2 PoS protocols face.&nbsp;Maintaining network service levels requires the efficient production of zk validity proofs. However, proofs are highly computationally intensive for the prover, which means that not every validator can be tasked with the computation. Randomly assigning the responsibility of producing a batch (L2 block) to a validator does not ensure optimal performance, which creates decentralization issues, as only pre-determined validators can be chosen.Proof of Efficiency (PoE) is a decentralised auction that is conducted automatically and the participants (coordinators) bid a number of tokens so that they have the chance to create the next batch. The strategic implementation of PoE promises to ensure that the network:<ul><li>Maintains its “permissionless” feature to produce L2 batches</li><li>Is efficient, a criterion which is key for the overall network performance</li><li>Attains an acceptable degree (Not maximum) of decentralization&nbsp;</li><li>Is protected from malicious attacks, especially by validators</li><li>Keeps a proportionate balance between the overall validation effort and the value in the network.</li></ul><h2 class="wp-block-heading">How does Polygon zkEVM reach consensus?</h2>A <a target="_blank" rel="noopener noreferrer" href="https://goerli.etherscan.io/address/0x5e2e663A39205348cE985Bccc9673Ca25AeE727E">Consensus Contract</a> (deployed on L1) utilizes a dedicated mechanism to verify that a set of predetermined rules have been followed for allowing state transitions. A smart contract verifies the validity proofs to ensure that each transition is completed correctly. For this to happen, there are two key participants in the network:Sequencers<ul><li>Roll-up the transaction requests in batches and add them to the PoE Smart Contract.&nbsp;</li><li>A Sequencer that proposes valid batches (which consist of valid transactions), is incentivised with the fee paid by transaction-requesters or the users of the network.</li><li>Anyone with the software necessary for running a zkEVM node can be a Sequencer.</li></ul>Aggregators<ul><li>Check the validity of the transaction batches and provide validity proofs.</li><li>In addition to running zkEVM’s zkNode software, Aggregators need to have specialised hardware for creating the zero-knowledge validity proofs utilizing zkProver.</li><li>An Aggregator that submits a validity proof earns the MATIC fee (which is being paid by the Sequencer of the batch).</li></ul><figure class="wp-block-image"><img src="https://lh3.googleusercontent.com/AWTde0ZYGwPsH0z9TUCvZZBN98JTiYY1UopNDy0VseccQvU8uRUpvM1UHssoXyWJaFUCNdyeZvF03_hbr2NwKk3o-1LBNdPMp-yKetpJ_pHdO2k63yJVIsY6SyNgyoveacgaBpzgqQVTXtvn1k5tKx4" alt="" decoding="async"></figure>The Smart Contract, therefore, makes two calls:<ul><li>One to receive batches from Sequencers</li><li>Another to aggregators, requesting that batches be validated.</li></ul><h2 class="wp-block-heading">This sounds great, but how can I connect to the Polygon zkEVM?</h2>Mainnet Beta is only going live on the 27th of March, 2023. In the meantime you can become familiar with the Public Testnet and play around with other dApps that are also currently running on testnet. To connect to the network, follow the steps below:<ul><li>Open up your Metamask wallet</li><li>Click the network name dropdown box at the top of your wallet</li><li>Click ‘Show/Hide’ test networks and enable it</li><li>Go back to the network selection dropdown and click ‘Add network’</li><li>Enter in the RPC details&nbsp; &nbsp;</li></ul><figure class="wp-block-image"><img src="https://lh5.googleusercontent.com/oVwyKYU115i_m69yl1c7MEpui7BS1imrEOClRfO8zZidKDeLNYP4IjQOLpYGZSoKajTqr_Ihzmit68aDCH5iVGlUWW-14Bt1ndQ7PdSbtsxPDyZ4WkP4_bBYZY9s49mJK3fLDZJP8pau3fJM_Pmo_48" alt="" decoding="async"></figure>Public Testnet Details<ul><li>ChainID: 1422</li><li>Network Name: Polygon zkEVM Testnet</li><li>RPC URL: https://rpc.public.zkevm-test.net</li><li>Currency Symbol: ETH</li><li>Block Explorer URL: https://explorer.public.zkevm-test.net</li><li>Broadcast gRPC: public-grpc.zkevm-test.net:61090</li><li>Bridge API: https://bridge-api.public.zkevm-test.net/</li></ul>Once you have connected to the network, you can deploy smart contracts to the testnet using your preferred scripting tool. Your basic RPC set-up will be the same. (Only cheaper and faster.)<h2 class="wp-block-heading">Conclusion</h2>Polygon zkEVM Mainnet is set to be the first fully EVM equivalent ZK rollup to reach mainnet. In the event of a successful launch, the network is poised to attract significant traction and acquire a first-mover advantage. Polygon has set the stage for other scaling solutions to rise to the occasion.

Decoding Polygon zkEVM: A Comprehensive Exploration

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