L{\O}: An Accountable Mempool for MEV Resistance

TL;DR

L{ extO} is a novel blockchain protocol that enhances accountability by accurately detecting and assigning blame for transaction manipulations like reordering, injection, or censorship, thereby mitigating MEV-related issues with minimal performance impact.

Contribution

L{ extO} introduces an accountable mempool protocol that detects and attributes transaction manipulations at the node level, improving transparency and security in blockchain systems.

Findings

L{ extO} effectively detects transaction reordering, injection, and censorship.

The protocol incurs only marginal performance overhead.

L{ extO} enables precise blame assignment to individual miners.

Abstract

Possible manipulation of user transactions by miners in a permissionless blockchain systems is a growing concern. This problem is a pervasive and systemic issue, known as Miner Extractable Value (MEV), incurs highs costs on users of decentralised applications. Furthermore, transaction manipulations create other issues in blockchain systems such as congestion, higher fees, and system instability. Detecting transaction manipulations is difficult, even though it is known that they originate from the pre-consensus phase of transaction selection for a block building, at the base layer of blockchain protocols. In this paper we summarize known transaction manipulation attacks. We then present L{\O}, an accountable base layer protocol specifically designed to detect and mitigate transaction manipulations. L{\O} is built around accurate detection of transaction manipulations and assignment of blame at the granularity of a single mining node. L{\O} forces miners to log all the transactions they receive into a secure mempool data structure and to process them in a verifiable manner. Overall, L{\O} quickly and efficiently detects reordering, injection or censorship attempts. Our performance evaluation shows that L{\O} is also practical and only introduces a marginal performance overhead.