Scroll (SCR) - The forefront of the Ethereum Layer 2 network

What is Scroll?

Scroll Project Introduction

Scroll is a Layer 2 solution based on zkRollup on Ethereum, aiming to improve its performance and availability to solve the congestion problem of Ethereum. Scroll was founded in 2021 by Ye Zhang, Sandy Peng, and Haichen Shen, with the vision of creating a zkEVM equivalent to EVM (Ethereum Virtual Machine) to achieve better compatibility.

Scroll Main Mechanism

First, let's briefly introduce a type of scaling solution called Zero-Knowledge Proof (zkRollup). To ensure the security of Rollup, it must prove that its off-chain computation (transaction processing) has been executed correctly. There are two main mechanisms for proving the validity of off-chain computation: Zero-Knowledge Proof (zkRollup) and fraud proof (optimistic Rollup): when zkRollup performs transaction computation and publishes the resulting state to L1, it also publishes validity proof. This mathematical proof can demonstrate that the resulting state is indeed the state generated after correctly executing a batch of transactions.

Scroll Zero-Knowledge Proof

Unlike all previous solutions, Scroll's Zero-Knowledge Proof system consists of two independent layers, using different Zero-Knowledge Proof systems. It can be understood as DApps proof aggregation and inter-layer recursion. The first layer directly generates proofs for different DApps. Scroll uses a universal and transparent Zero-Knowledge Proof system as the first layer, satisfying three properties: (1) Use short proof Secret Key (or non-proof Secret Key) for fast proof; (2) Unlimited scalability with low space complexity required; All DApps need to be set up. (3) The first requirement is to enable users to efficiently generate proofs, even by themselves. In this way, users can achieve privacy protection Smart Contracts with less proof effort in the future. Users can also outsource the proof generation work to Miners, who will efficiently generate proofs without the need to store a large amount of proof Secret Key for various DApps. The second and third requirements support all Smart Contract logics without the need for trust assumptions or computational effort. The second layer aggregates the proofs generated by the first layer and generates a concise proof for them. This is a wrapper layer; it can be viewed as a direct bridge between Scroll and Ethereum, satisfying two properties: (1) Short proof; （2）EVM friendly validation Algorithm. These two requirements make on-chain verification more efficient. The purpose of this wrapper is a universal on-chain validator. Through this wrapper, on-chain verification Smart Contract can be applied to various DApps. Miners will use a universal proof Secret Key to generate proof for this layer.

Rollup Process

Now let's take a look at the network structure of Scroll zk-rollup. Scroll Network consists of three main parts: Scroll Node, Roller Network, and Rollup contract.

1. The Scroll Node is responsible for collecting user transactions, constructing Blocks for the Rollup network, and submitting the created Blocks to the Ethereum blockchain, as well as passing messages between Ethereum and Rollup.
2. The Roller Network is a network composed of Rollers. Rollers act as provers to generate Zero-Knowledge Proofs, and Rollers are responsible for creating Block Proofs that represent the validity of a Block.
3. The Rollup contract is responsible for verifying the validation received from the Roller, receiving the state root and Block data summarizing the Scroll network status, and storing the state root and Block data in the ETH block state. Roll up process:

The Sequencer in Scroll Node continuously generates Blocks and provides the execution trace T to the Coordinator, and submits the Block data D to the Rollup contract existing in the Ethereum network. The Coordinator selects a random Roller existing in the Roller network and transfers T to it, and the selected Roller generates P, which is the Zero-Knowledge Proof of T. The generated P is sent back to the Coordinator, which collects P regularly and sends it to another Roller to create A, which is the digest of these Zero-Knowledge Proofs. Finally, the Coordinator receives A and submits it to the Rollup contract in Ethereum, where the Rollup contract verifies it and grants finality to the corresponding Block.

Block Final Consistency: When creating a Block, its finality is determined through several stages, and the state of the Block changes according to the process it is in:

• Pre-commit: The Block is proposed by the Sorter, and the T is passed to the roller's state. The Block has not been submitted to Ethereum. If the Sorter is trustworthy, the Block can be used directly in the pre-commit state.
• Submitted: Block data has been submitted to the state of the existing Rollup contract in the Ethereum network. This means that the Block data is available on the Ethereum network, but the validity of the operation cannot be guaranteed as the verification has not been confirmed yet.
• Final confirmation: The entire process described above has been fully completed and verified on the Ethereum network to the aggregated ZKP's state. As the validity of the operation has been proven on the Ethereum network, it is a complete state that can be safely trusted by anyone.

The status of Scroll's layer2

Before the project TGE, Scroll TVL exceeded 800 million US dollars, becoming one of the most prominent EVM compatible chains. The chain has achieved a bridging deposit of 367 million US dollars, and the rest are native assets. The chain reported a weekly active Address count of 255.52K. Scroll is also a profitable chain that reserves income for its validators. During peak periods, daily income reaches $100,000.

Scroll Financing Background and Partners

• On April 1, 2022, Scroll completed a Series A financing of 30 million, with investments from Polychain Capital, Bain Capital Crypto, and others; On 2023-03-06, Scroll completed a $50 million USD financing, with the investment round undisclosed, led by Polychain Capital and Sequoia Capital. Total Financing: 80 million US dollars The latest round of financing valuation: 18 billion US dollars The Scroll ecosystem is thriving, with most mainstream DApps expanding to its Mainnet, such as Lido, Ether.Fi, chainlink, AAVE, etc. Traditional DApps like Uniswap have also recently announced their participation in the ecosystem collaboration and are about to build applications on the Mainnet.

Scroll Token tokenomics

$SCR: Governance Token

$SCR will serve as the main governance mechanism for the protocol and evolve into a utility token for the Scroll Decentralization protocol.

1. Governance: Scroll will be governed by Scroll DAO Decentralization. Weighted decisions will be made in the community based on $SCR shares.
2. Proof of Authority: In order to ensure long-term sustainability, the protocol design incentivizes external parties to act as validators and optimizes their performance. $SCR will participate in aligning the Miner community and creating a robust network of validators.
3. Sorting Right: The sequential generator is responsible for sorting transactions and generating the second layer Block in a highly active and real-time review-resistant manner. $SCR will also serve as the bidding mechanism and incentive mechanism for sorting rights.

Token Allocation

$SCR is expected to start transfer and sale on October 22, and the initial total supply of Token will be 1 billion.

• Airdrop rewards: 15%
• Foundation: 10%
• Ecological Development: 35%
• Early contributors: 23%
• Investors: 17%

15% of SCR Token is used for Airdrop. The eligibility Snapshot will be conducted on October 19, and Airdrop claiming will start on October 22. The Airdrop is divided into two parts, with 7% of the Token used for the first Airdrop reward, and the remaining 8% reserved for future Airdrops. Visit the official website https://scroll.io/ to claim $SCR.

Gate.io lists $SCR Premint for pre-market trading, helping you stay ahead of the game

To welcome the upcoming listing of $SCR, gate has now opened the $SCR PreMint minting and $SCR PreToken trading, aiming to provide investors with the opportunity to position themselves early in popular tokens. The specific steps to participate are as follows:

1. Go to PreMint pre-trading page, stake USDT and mint $SCR.
2. Go to the $SCR trading page, and trade minted $SCR.
3. Upon the arrival of Delivery day, complete Delivery $SCR. gate $SCR PreMint For more details, please refer to the activity announcement: https://www.gate.io/announcements/article/39754