FOCIL Breakout #4

[soispoke]

Schedule

• Tuesday February 11th, 2025 @ 2pm UTC
• Duration 60 min
• Recurring meeting already on Ethereum Calendar
• Zoom Link

Agenda

• FOCIL Implementation Progress Tracker 👀
• Research updates: zkFOCIL, FOCIL <> Delayed Execution, FOCIL <> ePBS
• Implementation and testing updates
• Dora the explorer?

[poojaranjan]

Recording: https://www.youtube.com/live/2MkoP6BDNro

[jihoonsong]

Research

Privacy

• George, Benedict and Thomas published zkFOCIL that introduces an approach that allows includers to propose inclusion lists without revealing their identity. We really want to push this further and encourage anyone interested to reach out—either by applying to academic grants round or implementing a prototype.

Compatibilities with Other Proposals

• Thomas reviewed how FOCIL can work with Delayed Execution by Toni and Francesco and identified potential inherent incompatibilities. In Delayed Execution, blocks are validated while transactions are executed asynchronously. However, in FOCIL, if any IL transaction is missing in a payload, attesters should execute the payload to determine whether the missing transaction is invalid. Several possible solutions have been proposed but further research is needed.

• Terence reviewed how FOCIL can work with ePBS. There are different flavors in "delayed execution". One approach, as implemented by Toni and Francesco, changes the block to include the previous state root instead of the current one. Another approach decouples execution from the block, treating it as a separate object. This approach divides each slot into two parts: the first half is dedicated to the consensus block and the second half processes the execution payload. Although this is the strategy adopted by ePBS, it also introduces trade-offs for FOCIL. It reduces the time available for the IL committee to construct ILs or modifies the rules to enforce IL in the next slot rather than within the same slot.

• Both have different trade-offs. In the case of Delayed Execution, the primary concern is how to enforce IL constraints, whereas with ePBS, the focus is more on timing. Of course, these trade-offs require further research.

FOCIL Progress Tracker

• Jihoon and Thomas created a progress tracker for all clients. It allows everyone to easily check our current status. Jihoon and Thomas will update it frequently, so whenever you’d like your progress reflected, please let them know.

Implementation Updates

• Nethermind is working on interop with Prysm.
• Lodestar finished basic implementation, reviewed code internally and tried interop with Geth. There was a bug in Geth, which has been fixed. Lodestar <> Geth local devenet works fine but a state root mismatch problem occurs when Prysm is added to the local devnet that both Prysm and Lodestar are rejecting each other's blocks.
• Prysm has tested happy case, encountered the same issue with Geth, which has been fixed, and is now undergoing refactoring and testing.
• Reth <> Lodestar works in happy case and additional test cases are in progress. Running a local devnet of Reth <> Lodestar and Reth <> Prysm suffers from the state root issue.
• Lighthouse is currently working on interop with Geth and expects to join Prysm and Lodestar by the end of this week.
• Teku is under development but after implementing fork-choice and beacon APIs, they're ready for interop.

Issue with Dora

• Dora doesn't recognize eip7805 block so CLs had to hard-code beacon block's version to electra. This was due to a miscommunication and Dora will alias eip7805 as electra.

PEEPanEIP

• Thomas and Julian had a podcast with Pooja. A recording should be published in this week.

Questions

• Is zkFOCIL going to change EIP-7805? No, it's in the early research phase and won't hold FOCIL back. It's part of FOCIL endgame.

Links

• FOCIL Progress Tracker
• zkFOCIL: Inclusion List Privacy using Linkable Ring Signatures
• Call for participation for privacy research—academic
• Call for participation for privacy research—implementation
• FOCIL meets Delayed Execution
• FOCIL with Delayed Execution under EPBS (EIP-7732)

[poojaranjan]

PEEPanEIP recording