Assess whether randomized ordering survives in concurrent DAG consensus

Determine whether replacing deterministic intra-round ordering with randomized ordering can preserve its intended fairness properties in a live, concurrently constructed directed acyclic graph while remaining compatible with data-dependent transactions and acceptable computational costs.

Background

The paper examines MEV attacks that exploit deterministic inter-block ordering in DAG-based Byzantine fault-tolerant protocols. It discusses randomized leader or committee selection and randomized ordering based on on-chain randomness and block digests as possible defenses against predictable ordering advantages.

The authors note that randomization may disrupt the happen-before relationships needed by data-dependent transactions and may introduce computational overhead. Although it appears promising against the deterministic tiebreak mechanisms studied in the paper, its behavior in a live, concurrently constructed DAG remains unresolved.

References

Of the four directions, this one comes closest to the lever we study, since it targets the same deterministic tiebreak we replace in \S\ref{sec:mitigation:fix}. Its costs are real: discarding the happen-before relationship among blocks can break data-dependent transactions, and randomization adds computation. Whether it survives contact with a live, concurrent DAG is open.

— Competition, Collusion, and Corruption: The Spectrum of MEV Attacks on DAG-Based BFT Consensus Protocols  (2609.20069 - Mirzaei et al., 17 Sep 2026) in Section 6, “Mitigations and Their Limits,” paragraph “Spread out who proposes”