Overview
The FOCIL (Fork-choice enforced Inclusion Lists) protocol development team has identified several open research problems that need solving. FOCIL is EIP-7805, a censorship resistance mechanism that allows a committee of validators to force-include a set of transactions in every block.
Open Problems
- FOCIL Transaction Fee Mechanism
What is the best way to charge fees and distribute these fees for inclusion in the inclusion list? How should "best" be defined?
- Compatibility with other protocol upgrades
We need to assess the potential synergies and conflicts between FOCIL and other protocol upgrades like Account Abstraction (EIP-7702), ePBS (EIP-7732), PeerDAS (EIP-7594), etc.
Inclusion lists must likely be bounded in size to prevent excessive bandwidth usage. How do we determine the optimal size of the inclusion lists?
- Multi-slot MEV Prevention via FOCIL
FOCIL enables multiple proposers to force include transactions into a block. What types of multi-slot MEV does this prevent?
FOCIL Properties
- Committee-based: FOCIL relies on a committee of multiple validators, rather than a single proposer, to construct and broadcast ILs. This approach significantly reduces the surface for bribery and extortion attacks and strengthens censorship resistance.
- Fork-choice enforced: FOCIL incorporates the force-inclusion mechanism into the fork-choice rule, an integral component of the consensus process, thereby preventing any actor from bypassing the system.
- Same-slot: With FOCIL running in parallel with the block building process for slot N+1 during slot N, the constraints imposed on block B for slot N+1 can include transactions submitted during slot N.
- Conditional inclusion: FOCIL adopts conditional inclusion, accepting blocks that may lack some transactions from ILs if they cannot append the transactions to the end of the block or if they are full.
- Anywhere-in-block: FOCIL is unopinionated about the placement of transactions from ILs within a block. This reduces incentives for sophisticated actors to use side channels to bypass the mechanism.
- No incentive mechanism: FOCIL does not provide explicit rewards for IL committee members participating in the mechanism.
Resources
Contact
Anything missing? Please message Jihoon Song on Twitter.