Experience the Ethereum Layer 2 network Scroll Pre-Alpha testnet in advance
The Scroll Pre-Alpha testnet has launched features such as trading, cross-chain, and a browser for Layer 1 and Layer 2. Let's experience it.Author: Babywhale, Foresight News
In 2022, several scaling networks and new public chains gained market attention and capital favor. This includes a public chain developed by former team members of the original Facebook (now Meta) digital currency project after the team was disbanded, the establishment of EVM-compatible sidechains for non-EVM compatible public chains, as well as projects related to layer two networks. It also includes the Ethereum layer two network based on ZK Rollup, which was personally "endorsed" by Ethereum founder Vitalik Buterin.
In April of this year, the Ethereum layer two network Scroll, based on ZK Rollup, completed a 30 million dollar Series A funding round led by Polychain Capital, with participation from Bain Capital Crypto, Robot Ventures, Geometry DAO, and others. Three months later, Scroll announced the launch of its Pre-Alpha testnet and opened applications. This month, Scroll upgraded the testnet, allowing for the deployment of smart contracts and cross-chain transfers of NFTs and ERC-20 tokens.
Currently, the Scroll Pre-Alpha testnet has launched features such as trading, cross-chain functionality, and a browser for Layer 1 and Layer 2. Let's experience it together.
First, users who have obtained testnet access through application need to add Layer 1 and Layer 2 testnets on MetaMask via the testnet homepage and claim test tokens like ETH and USDC through the Faucet.
After adding the networks and claiming test tokens, users can first test the cross-chain functionality by clicking on "Bridge" at the top of the testnet website. We will take transferring 100 USDC from Layer 1 to Scroll Layer 2 as an example.
The transaction confirmation on the testnet Layer 1 took about 10 seconds. Although there is a certain waiting time for the cross-chain transfer to Layer 2, it still shows a significant speed advantage compared to the 7-day confirmation time of the official cross-chain bridges of Optimism and Arbitrum. (Recommended reading: “Understand Scroll in Three Minutes: A New Contender for ZK Rollup Scaling”)
After the cross-chain transaction is confirmed, users can click on their personal address in the upper right corner to view transaction information.
Once the assets have been transferred from Layer 1 to Layer 2, users can test the token trading functionality on Layer 2.
As with all DEX trades, users need to pay gas fees to allow the contract to call the traded tokens before proceeding with the transaction. It is worth mentioning that Scroll's Pre-Alpha testnet has integrated the oracle RedStone, which raised 7 million dollars, allowing developers to apply for testing qualifications to deploy smart contracts for testing.
The gas fee for this transaction was approximately 0.00021 ETH, which, at Ethereum's current price of 1600 dollars, amounts to about 0.336 dollars. At the time of writing, the gas fees for transactions on Arbitrum One are about 0.07 dollars, Optimism is 0.15 dollars, and zkSync is 0.1 dollars. Although Scroll's price appears higher based on simple data comparison, considering the current limited number of testnet nodes but a high volume of transactions, the actual data may have significant room for decline.
After experiencing trading, users can next try adding liquidity in the test DEX. By clicking "Pool" on the trading page and then "Add Liquidity," we will also take adding 100 USDC and an equivalent value of ETH as an example.
After adding liquidity, users can view their liquidity positions on the page.
In addition to cross-chain transfers and trading, the Scroll testnet also provides a browser for Layer 1, Layer 2, and Rollup.
The ordinary block explorer needs no further explanation, but the key point is that Scroll provides a special data interface known as the Rollup browser.
The three data points above represent the following: the first data indicates the block height on Layer 2; the second data refers to the block that has been submitted to the Layer 1 Rollup contract; the third data represents that the validity proof of that block has been submitted and verified on Layer 1.
Transactions on Layer 2 are categorized into four states:
Precommitted indicates that the block has been included in the Scroll Layer 2 blockchain. Although Precommitted blocks have not yet been published on Layer 1 and thus are not part of the Scroll Layer 2 canonical chain, users who trust the Sequencer can consider this block as preliminarily finalized.
Committed indicates that the transaction data of the block has been published on the Layer 1 Rollup contract. This ensures that the block data is available, but it does not prove that it has been executed in a valid manner.
Finalized indicates that the correct execution of the transactions in the block has been proven through on-chain validity proofs on Layer 1. Finalized blocks are considered part of the Scroll Layer 2 canonical chain.
Skipped indicates that the validity proof generation for the block was skipped due to a lack of proof capability or errors in the code. This is merely a temporary state of the Pre-Alpha testnet.
