How can Ethereum PoS be improved?

Ethereum has been a stable operating proof-of-stake system for nearly two years, demonstrating excellent performance in terms of stability, performance, and avoiding centralization risks. However, proof-of-stake still has some important areas that need improvement. This article will focus on what aspects of the technical design of proof-of-stake can be improved and what approaches can be taken to achieve these improvements.

Single-slot finality and staking democratization

Currently, Ethereum requires 2-3 epochs ( about 15 minutes ) to finalize a block, and 32 ETH is needed to become a validator. This is a compromise made to strike a balance between maximizing the number of validators that can participate in staking, minimizing completion time, and minimizing the costs of running nodes.

Ideally, we hope:

• Complete block finality within a time slot ideally in 12 seconds or less (
• Allow validators to stake 1 ETH, reducing from 32 ETH to 1 ETH)

These two objectives conflict with the goal of minimizing costs. To address this, there are several leading solutions:

1. Brute Force: Striving to achieve a better signature aggregation protocol, possibly using ZK-SNARKs, allowing for the processing of a large number of validators' signatures in a short time.

2. Orbit Committee: Allows a randomly selected medium-sized committee to finalize the chain, but in a way that preserves the cost attribute of attacks.

3. Two-tier staking: Stakers are divided into two categories, one with higher deposit requirements and the other with lower. Only the tier with higher deposit requirements directly participates in providing economic finality.

4. Mixed Scheme: Multiple strategies can be combined.

Single Secret Leader Election

Currently, which validator will propose the next block is known in advance, which creates a security vulnerability. The solution is to hide which validator will generate the next block's information, at least before the block is actually generated.

The Single Secret Leader Election Protocol addresses this issue by creating a "blind" validator ID for each validator using cryptographic techniques, and then allows multiple proposers the opportunity to reshuffle and re-blind the pool of blind IDs. In each time slot, a random blind ID is selected, and only the owner of that blind ID can generate a valid proof to propose a block.

The main challenge in achieving this goal is to find and implement a protocol that is simple enough to be easily implemented on the mainnet, without excessively increasing the complexity of the Ethereum protocol.

Faster Transaction Confirmation

Reducing the Ethereum transaction confirmation time from 12 seconds to 4 seconds will significantly improve the user experience for L1 and aggregation-based solutions, making DeFi protocols more efficient and facilitating the decentralization of L2.

There are mainly two technical routes:

1. Reduce the time slot duration, for example, to 8 seconds or 4 seconds.
2. Allow proposers to publish pre-confirmations during the time slot process.

The main challenge of reducing time slots is that it may lead to validator centralization. The pre-confirmation method can improve the average inclusion time, but it cannot improve the worst-case inclusion time. In addition, how to incentivize pre-confirmation is also a problem that needs to be addressed.

Other Research Areas

1. 51% attack recovery: Reduce reliance on social layers to make the recovery process as automated as possible.

2. Increase the quorum threshold: Consider raising the required support rate from 67% to 80% to enhance security.

3. Quantum Resistance: Develop quantum-resistant alternatives to prepare for potential quantum computing threats in the future.

These improvements will further enhance the security, efficiency, and decentralization of Ethereum PoS, laying a more solid foundation for the long-term development of Ethereum.