- Ethereum has to process 1,790,000 signatures after single slot finality
- Fork choice fixes are much more complex because you can’t extract signatures
- The minimum deposit size could be raised to 4096 ETH with 4096 validators
Ethereum cofounder Vitalik Buterin wrote about a major difference between Ethereum and most other proof of stake systems, namely that Ethereum has almost 900,000 validator objects. This is an astronomic number of validators. While the goal is to support decentralization, it also requires the Ethereum Mainnet to process a very high number of signatures (1,790,000 after single slot finality, or SSF) per slot.
Technical sacrifices
This load comes with many technical sacrifices. Buterin wrote a post on the semi-public forum Ethresearch that it requires a complex attestation propagation setup, which involves splitting attestations up between multiple subnets, having to hyper-optimize BLS signature operations to verify signatures, etc.
Other downsides of the load:
· Fork choice fixes are much more complex because you can’t extract signatures
· There is no efficient drop-in quantum-resistant alternative
· The minimum staking requirement of 32 ETH is unattainable for most users.
This is why Buterin proposes reducing the number of sigs needed. He says this would expand the PoS design space a great deal. Among other things, it would increase Helios security by letting it SNARK over Ethereum consensus directly, simplify technical aspects, etc.
To this end, he had three ideas:
1. Fully decentralize all staking pools
The minimum deposit size could be raised to 4096 ETH with a total cap of 4096 validators. Small-scale stakers would join a DVT pool by becoming node operators or by providing capital.
Pools would compete through different options to prevent hacks and other attacks. Capital provision would be permissionless.
2. Adopt two-pronged staking
The second strategy would be to create two staking layers: a heavy one and a light one. The former would take part in finalization and comply with the 4096 ETH requirement. The latter would add a second security layer, no delayed deposits and withdrawals, and no slashing vulnerability.
3. Set up rotating participation
The final approach is selecting 4096 currently active validators and adjusting the set carefully during each slot to ensure safety.
