Vitalik Buterin, co-founder of Ethereum, has recently written an article discussing three methods to accelerate transaction confirmation times on Ethereum and proposes three reasonable development strategies for Layer2.
Table of Contents:
1. Single Slot Finality to accelerate “final confirmation” time
2. Rollup pre-commitment and Based pre-commitment
3. Three development directions for Layer2
In his latest article, Vitalik Buterin explores several methods to improve transaction confirmation times on Ethereum, including Single Slot Finality (SSF), Rollup pre-commitment, and Based pre-commitment mechanisms. He emphasizes the importance of slot and epoch structures in providing fast transaction confirmations.
Buterin states that one of the important features of a good blockchain user experience is fast transaction confirmation times. Over the past five years, Ethereum has made significant improvements in this aspect, especially with the introduction of EIP-1559 and the Merge, which have stabilized block times. Transactions on Layer1 can now be confirmed within 5-20 seconds, comparable to the experience of credit card payments.
However, further improvements in user experience are still needed, particularly for applications that require millisecond-level or lower latency. The following discusses some practical options for improving transaction confirmation speed on Ethereum.
First, Buterin suggests Single Slot Finality (SSF) as an alternative to the existing Gasper consensus mechanism. The Gasper consensus mechanism currently allows transactions to be confirmed within 5-20 seconds, but the 12.8-minute finality time is considered too long. The SSF mechanism, which is closer to the Tendermint consensus, allows the previous block to be finalized before a new block is formed and allows the blockchain to continue running through an “inactive leakage” mechanism, recovering when more than one-third of validators are offline.
The main challenge of SSF is the potential increase in network load, as it requires all Ethereum stakers to publish two messages in each 12-second slot. The Orbit SSF proposal is a powerful solution to address this issue. While it significantly improves user experience by speeding up finality, it doesn’t change the fact that users still need to wait 5-20 seconds.
In addition, Buterin also discusses the mechanisms of Rollup pre-commitment and Based pre-commitment. Ethereum has been following a Rollup-centric development path, where Layer1 is designed to support data availability and other functions, while Layer2 provides larger-scale services for users. However, this poses an inevitable problem: L2 needs to provide services for users who require faster confirmation speeds than 5-20 seconds.
Furthermore, requiring all L2 solutions to implement decentralized ordering networks is unfair and essentially requires them to do most of the work of a new Layer1. To address this problem, Justin Drake has introduced a shared pre-commitment mechanism based on Ethereum called Based pre-commitment, which can be accessed by all L2 and L1.
Based pre-commitment assumes that Ethereum proposers will become highly complex participants due to MEV (Maximal Extractable Value) related reasons. Leveraging this complexity, the based pre-commitment method incentivizes these experienced proposers to provide pre-commitment services. The basic idea is to create a standardized protocol where users can pay additional fees to guarantee that their transactions will be included in the next block and potentially make statements about the outcome of the transaction execution. If the proposers violate any commitments to users, they will be penalized.
In summary, Based pre-commitment provides guarantees for L1 transactions. If a Rollup is “Based,” then all L2 blocks are L1 transactions, allowing the same mechanism to provide pre-commitment for any L2.
Lastly, Buterin proposes three reasonable development strategies for L2:
1. Ethereum-centric on both technical and ideological levels: These L2 optimizations pass on the technical attributes and values (decentralization, resistance to censorship, etc.) of Ethereum’s base layer. In simple terms, these rollups can be seen as “branded shards” and can be used for extensive experimentation in new virtual machine designs and other technical improvements.
2. Server-based blockchain architecture: These L2 solutions start from servers and then add STARK validity proofs, user exits or the right to force transactions, and the freedom of collective choice (such as coordinating large-scale exits or changing the orderers). They gain the benefits of running a large number of chains while maintaining server efficiency.
3. Compromise solutions: Adopting a fast chain with hundreds of nodes, Ethereum provides additional interoperability and security, which is the practical roadmap for many L2 projects.
According to Buterin, the key question is how well we can do in the first category. If the first category becomes very good, the significance of the third category may diminish. The second category will always exist because any “Ethereum-based” solution does not apply to L2 solutions like plasmas and validiums that handle off-chain data.
In conclusion, Buterin emphasizes the need for more choices to simplify the work of L2 developers and improve the user experience.