Analysis of Multi-Chain Account Abstraction Technology: The Future Direction of Encryption Infrastructure Development

From July 8 to 11, 2024, the largest annual Ethereum technical conference in Europe will be held in Brussels, Belgium. This conference brings together over 350 top experts in the blockchain industry to give speeches, focusing on technological innovation and community development.

A blockchain developer delivered a speech titled "Revealing the Future: An Analysis of Multi-Chain Account Abstraction" at the conference, delving into the core concepts of account abstraction technology, different implementation methods, and its application differences across various chains.

Account Abstraction Technology Overview

Account abstraction ( AA ) technology primarily focuses on two core aspects: signature abstraction and payment abstraction.

• Signature abstraction allows users to freely choose the verification mechanism, no longer limited to specific digital signature algorithms.
• Payment abstraction offers a diverse range of transaction payment options, such as paying with ERC-20 tokens or introducing third-party sponsored transactions.

This flexibility greatly enhances user experience and security.

Interpretation of ERC-4337 Standard

The ERC-4337 standard addresses some inherent limitations of externally owned accounts (EOA) on Ethereum by introducing more flexible account management and transaction processing methods. Its core components include:

• userOp structure: Users package operation information into the userOp structure and send it to the Bundler.
• Bundler: Collects multiple userOps and calls the handleOps function of the EntryPoint contract.
• EntryPoint contract: responsible for verifying userOp, collecting fees, and executing target operations.

Native Account Abstraction

Some blockchain networks adopt a native account abstraction design, treating each account as a contract and embedding the transaction processing mechanism directly into the blockchain protocol.

Different network implementations of AA:

• Account abstraction following ERC-4337: Ethereum and multiple Layer 2 networks
• Native account abstraction following ERC-4337: Certain ZK Rollup networks
• Native account abstraction with privacy design: a certain anonymous network

Main Differences Between ERC-4337 and Native Account Abstraction

1. Operating System Role: ERC-4337 is completed through the collaboration of Bundler and EntryPoint contracts, while native account abstraction is handled by the operators/relayers of the official server.

2. Contract Interface: The entry point function of the verification phase remains consistent across implementations, but only the native AA fixed the entry point during the execution phase.

3. Verification Step Limitations: Different implementations have varying degrees of restrictions on usable opcodes and storage access to prevent potential DoS attacks.

4. Execution Step Limitations: Some networks require confirmation system flags to perform specific operations, while others have no special restrictions during the execution phase.

5. Random Number Management: Different implementations use their own nonce management mechanisms, some allow flexible settings while others require strict increments.

6. First Transaction Deployment: ERC-4337 allows for the deployment of an account contract in the first userOp, while some native account abstraction implementations require a separate deployment transaction.

Differences in the Implementation of ERC-4337 on L1 and L2

There are two key differences when implementing ERC-4337 on EVM-compatible chains:

1. Protocol differences: Layer 2 solutions need to upload data to Layer 1 to ensure security and final settlement, which involves additional cost calculation issues.

2. Address calculation differences: Different networks use different address encoding methods, which may result in inconsistencies in the addresses of the same contract on different chains. Especially when a hard fork introduces new opcodes, if the EVM version is not specified, unexpected bytecode changes may occur.

This presentation provided us with an in-depth analysis of the core concepts of account abstraction technology and the differences in multi-chain implementation, offering valuable insights for the development of future encryption infrastructure. As technology continues to evolve, we look forward to seeing more innovative applications that further enhance the user experience and security of the blockchain ecosystem.