Comparison and Analysis of Bitcoin Layer 2 Solutions: Finding the Best Scaling Path

Recently, Bitcoin Layer 2 has become the hottest topic in the cryptocurrency market, with various BTC L2 projects emerging one after another. This article will conduct an in-depth comparative analysis of the current mainstream five types of BTC L2 solutions from a technical implementation perspective, including Bitcoin sidechains, UTXO + client verification, Taproot Consensus, multi-signature + EVM, and Rollup.

We will evaluate the pros and cons of these solutions from three dimensions: the native nature of Bitcoin, the degree of decentralization, and the level of implementation. The native nature of Bitcoin reflects adherence to the core principles of Bitcoin, determining whether it can gain recognition from the Bitcoin community. The degree of decentralization concerns the security management of BTC and is key to whether BTC Layer 2 can gain user trust. The level of implementation serves as a direct standard for assessing the feasibility of the solution.

1. Bitcoin Sidechain

Bitcoin sidechains are expansion blockchains that operate independently of the Bitcoin main chain, typically managing Bitcoin through methods such as multi-signature or Hash Lock, and mapping BTC on layer 2 to support complex scenarios.

Bitcoin native quality: poor, difficult to obtain support from the Bitcoin community. Decentralization level: Average, asset security relies on multiple signers. Level of implementation: Although it has existed for many years, the ecological development results are limited.

2. UTXO+ Client Verification

The solution is based on the Bitcoin UTXO model for off-chain ledger computation, using client-side verification to ensure the authenticity of the ledger. Typical representatives include RGB and BitVM.

Bitcoin's native property: very high, but overly emphasizing native property leads to extreme difficulty in implementation. Degree of decentralization: relies on decentralized client validation, non-consensus decentralization. Implementation level: still in the theoretical stage, facing huge uncertainties in implementation.

3. Taproot Consensus

Taproot Consensus is built on three native technologies of Bitcoin: Schnorr signatures, MAST contracts, and a lightweight node network. BEVM is a typical practice of this solution.

Bitcoin Native Nature: Extremely high, completely based on Bitcoin's mature technology. Degree of decentralization: Achieve decentralized BTC management through 1000+ Bitcoin light nodes. Degree of implementation: BEVM has been running stably for several months, handling a large number of transactions, and the ecosystem has begun to take shape.

4. Multi-signature + EVM

The plan is to deposit BTC into a multi-signature address and map new BTC on the EVM chain. The implementation is simple, but the essence is still a sidechain.

Bitcoin's native nature: almost none, Layer 2 can be completely independent of Bitcoin. Decentralization level: Asset security completely relies on the multi-signers designated by the project team. Implementation Level: Low technical threshold, easy to achieve, but requires high management capability for multi-signers.

5. Rollup

The Ethereum Layer 2 solution will be introduced to Bitcoin, but Bitcoin cannot verify Rollup data and requires an additional verification mechanism.

Bitcoin native nature: poor, difficult to gain support from core Bitcoin users. Degree of decentralization: The decentralization issues of asset management and Layer 2 ledgers have not yet been resolved. Degree of implementation: the technology is relatively mature, some projects have reached a certain scale, but still face trust challenges.

Summary

The five types of BTC L2 solutions each have their own advantages and disadvantages. Bitcoin sidechains are hard to gain recognition; multi-signature + EVM is easy to implement but lacks decentralization; UTXO + client validation has strong native properties but is difficult to implement; Rollup draws on Ethereum's experience but has not solved the fundamental problems. In contrast, Taproot Consensus performs well in terms of native properties, decentralization, and implementability, making it a more feasible BTC L2 solution.