Vitalik's post-merge Ethereum blueprint 4 The Verge: Verkle Trees implement stateless verification, Apple Watch can also serve as a node

Ethereum co-founder Vitalik Buterin has recently been writing a series of articles about the future blueprint of Ethereum. In the fourth article on "The Verge", he introduced the concept of a decentralized blockchain validation network, which is also the vision of The Verge.

Vitalik stated that a powerful feature of blockchain technology is that anyone can run a node on their computer and validate the correctness of the blockchain. Even if 95% of the nodes attempt to change the rules, users running full validation nodes can still reject the new blockchain and continue to follow the old rules. This decentralized feature is one of the core advantages of blockchain over centralized systems. However, the premise of this advantage is that running a full validation node must be feasible for the majority of people.

Currently, while running a node on consumer-grade laptops is possible, it is not easy. The mission of The Verge is to simplify this process, making the cost of running full validation low enough so that every mobile wallet, browser wallet, and even smartwatch can automatically perform blockchain validation.

Vitalik's post-merge Ethereum blueprint 1: Considering consensus modifications to increase finality speed

Vitalik's post-merge Ethereum blueprint 2: Targeting 100,000 TPS, reviving Plasma off-chain scaling, and integrating the L2 ecosystem

Verge's 2023 Roadmap: Innovating Verification Technology with Verkle Trees

Initially, "Verge" referred to the transition of Ethereum state storage to Verkle Trees, a structure that allows for more compressed proofs, making stateless validation of blocks possible. Verge now encompasses a grand vision of verifying the entire Ethereum execution through zero-knowledge succinct non-interactive arguments of knowledge (SNARKs) technology.

Regarding statelessness: It's not just about blockchain! How stateless infrastructure brings efficiency to decentralized networks.

Stateless Verification: Verkle Trees and STARK Technology

What Problems Do Verkle Trees Solve?

Vitalik stated that Ethereum nodes currently need to store hundreds of gigabytes of state data to verify blocks, which is a significant technical burden for many users. With data growing annually, regular users' computer storage is limited, making running full verification nodes difficult. This not only reduces the number of node operators but also makes the synchronization process for new nodes complex and time-consuming.

How Verkle Trees Operate

Stateless verification transmits each block with proof data, allowing nodes to verify blocks without storing the entire state. This verification process necessitates a change in the current Ethereum state tree structure as the existing Merkle Patricia tree is not suitable for efficient cryptographic proofs. Therefore, the current focus is on using Verkle Trees or STARKed binary hash trees.

Breakthroughs and Challenges of Verkle Trees Technology

Advantages of Verkle Trees

Vitalik explained that Verkle Trees ensure shorter proofs by using elliptic curve-based vectors, theoretically significantly reducing proof size. This technology allows for less data transmission between nodes, thereby reducing the cost of node synchronization and verification.

Challenges of Verkle Trees

Vitalik believes that although Verkle Trees excel in proof size, their resistance to quantum computers is weaker, indicating a potential need for further upgrades to quantum-secure technology in the future. Additionally, in worst-case scenarios, proof data may still be too large, especially when facing malicious node attacks, making this technology still somewhat risky in certain contexts.

STARKed Binary Hash Trees: Another Future Option

Vitalik stated that STARKed binary hash trees technology is an alternative solution that significantly reduces the amount of data required for verification by generating proofs. While this technology has potential, its main challenge lies in the lengthy computation time required to generate proofs, especially needing further optimization on current hardware for large-scale applications to be feasible.

Key Goals and Future Applications of Verge

Whether adopting Verkle Trees or STARKed binary hash trees, the goals are as follows:

1. Stateless Clients: Allowing full verification clients and verification nodes to run without the need to store large amounts of state data.
2. Full Verification on Smartwatches: The long-term goal is to enable devices like smartwatches to download minimal data and verify the entire chain.

Moreover, Verge technology will be applied in several key areas:

• Transaction Pool: Verification nodes need to confirm the validity of transactions before relaying them, and stateless verification technology can streamline this process.
• Light Clients: Verge technology can enable light clients like wallets such as Metamask to verify transactions without relying on centralized services.

Optimization Goals for Ethereum Validity Proofs

EVM Execution Layer Validity Proofs

The ultimate goal is to make Ethereum block verification highly resource-efficient. Users would only need to download minimal data and verify a small proof to confirm block validity, making the use of lightweight clients more widespread and feasible.

Consensus Layer Validity Proofs

Ethereum's consensus layer proof involves verifying stakers' signatures, processing deposits and withdrawals, etc. While the consensus layer is relatively simple, its verification still needs to address efficient computation of BLS signatures and SHA256 hashes. Future challenges will focus on further optimizing these processes to achieve low-resource and efficient consensus verification.

Overall, Verge represents a key milestone for Ethereum's future, not only symbolizing technological breakthroughs but also offering new possibilities for Ethereum's decentralization and scalability.