in a detailed blog post Dated December 27, ethereum founder Vitalik Buterin outlined a significant change in ethereum's approach to proof-of-stake (PoS) validation following its upgrade in Shanghai.
ethereum currently supports many validators, with approximately 895,000 validation objects allowing for a broad base of participation from individuals and entities. This is a key feature of ethereum's decentralized structure.
However, this model presents technical challenges, particularly the processing of an immense number of signatures. Today about 28,000 signatures are needed to validate a block; That number is expected to reach 1.79 million after SSF (Sharding and Staking Finality).
The technical sacrifices to support such a load are considerable. They include complex attestation propagation mechanisms, the need for hyper-optimized BLS signature operations, the lack of a viable quantum-resistant alternative, and increased slot times due to more subslots.
Buterin also highlights the systemic complexity of the current model and its potential ineffectiveness in truly democratizing staking, as the minimum staking requirement of 32 eth remains financially prohibitive for many.
8,192 signatures
In response, Buterin proposes a pivot that would reduce the number of signatures per space to a manageable 8,192. He maintains that this change would open up the PoS design space, enable technical simplification, improve security, and address quantum resistance issues.
Buterin criticizes the committee-based security approach used by other blockchains, emphasizing the lack of accountability and insufficient deterrents against attacks. ethereum, on the other hand, imposes severe penalties on attackers. Still, Buterin suggests that even a reduced attack cost (1-2 million eth) would be sufficient, advocating for a balanced solution that maintains high penalties but offers more benefits than a smaller set of validators.
The blog post explores three approaches to implementing the 8192 signatures per slot in SSF:
- Decentralized Betting Pools– Focus solely on decentralized stakeholder groups, potentially increase minimum deposit size, and limit penalties to reduce trust in node operators.
- two tier stake: Establish a “heavy” layer for key stakeholders involved in completion and a “light” layer for additional security, with no minimum involvement requirements.
- Rotating participation (Responsible Committees): A hybrid approach where validators participate based on their interest, ensuring security through carefully tuned sets of validators.
Buterin's conclusion emphasizes that limiting itself to 8,192 signatures would greatly simplify the technical implementation and make ethereum more accessible. The focus would then be on choosing the most appropriate approach among the proposed options.
Security through simplicity
Some users expressed concerns in the comments about designing systems that are resilient against state attackers, suggesting that even a reduced security budget could be insufficient. Buterin responded by emphasizing the importance of simplicity in protocol design as a means of defense against various attack vectors, advocating “security through simplicity.”
This proposed change signifies a pivotal moment in the continued development of ethereum, highlighting the ongoing balance between security, decentralization, and usability.
