Written by: Haotian
How to understand @VitalikButerin's thinking on Ethereum transaction confirmation method? Because the transaction confirmation time of the main network of 5-20s is close to the speed of credit card consumption, it seems to be enough from the user's perception. But compared with the confirmation time of layer2 at the millisecond level, the difference in transaction confirmation between the main network and layer2 will have certain security risks. Therefore, optimizing the transaction confirmation time of the main network is more to cater to the consideration of the development strategy of layer2?
1) Ethereum's current Gasper consensus mechanism adopts the core concepts of Slot (time slot) and Epoch (period). Each Slot lasts for 12s, and a part of Validators will be selected to verify the current transaction status of the chain for voting. Every 32 Slots, that is, 6.4 minutes, will constitute a period. Basically, all validators in a period will complete the voting. The finality of the transaction usually takes two periods, that is, 12.8 minutes, which means that a transaction will have irreversible characteristics only 12.8 minutes after it is initiated.
2) Vitalik believes that the time is too long and is dissatisfied with the current Gasper consensus mechanism. He proposed a Single-slot finality improvement method, which can ensure that each block completes finality confirmation before the next block is generated, so the finality confirmation time can be accelerated. However, final confirmation and transaction confirmation are two different things, which is not closely related to the 5-20s transaction confirmation perceived by users, but if it corresponds to the layer2 network, the problem will be big.
3) Because the time for layer2 users to submit and confirm transactions will be shorter, it is not only better than the user-perceived time of 5-20s, but may reach the millisecond level. This is due to the pre-transaction confirmation mechanism adopted by layer2 as a whole. However, if the final confirmation time of the layer1 mainnet transaction is too long, there will be some time difference risks on layer2 in theory: for example, the user quickly confirmed and took subsequent actions on L1, but may lose funds due to the delay in the confirmation of the status of L1; moreover, since layer2 itself has certain centralized risks, the longer the time difference, the greater the potential risk of centralization.
4) Therefore, in my opinion, Vitalik's new article on the optimization of the Ethereum mainnet transaction confirmation time is, to some extent, to cater to the grand strategy of the layer2 system and the layer1 system to jointly promote. Although some people in the market are singing the pessimism of layer2, layer2 has become a direction that must be stabilized in the development of Ethereum.
Obviously, Ethereum will definitely be promoted by the "layered" strategy in the future. It will be the general trend to rely on layer1 to focus on security and decentralization, and rely on layer2 to provide a stable and reliable interactive settlement environment. Vitalik proposed to speed up transaction confirmation, which is essentially to reduce the layer friction between layer1 and layer2, and provide users with a better front-end interactive environment for layer2 experience and a more secure back-end settlement foundation.