Demand for blockchains such as Bitcoin and Ethereum is far larger than supply, necessitating a mechanism that selects a subset of transactions to include "on-chain" from the pool of all pending transactions. This paper investigates the problem of designing a blockchain transaction fee mechanism through the lens of mechanism design. We introduce two new forms of incentive-compatibility that capture some of the idiosyncrasies of the blockchain setting, one (MMIC) that protects against deviations by profit-maximizing miners and one (OCA-proofness) that protects against off-chain collusion between miners and users. This study is immediately applicable to a recent (August 5, 2021) and major change to Ethereum's transaction fee mechanism, based on a proposal called "EIP-1559." Historically, Ethereum's transaction fee mechanism was a first-price (pay-as-bid) auction. EIP-1559 suggested making several tightly coupled changes, including the introduction of variable-size blocks, a history-dependent reserve price, and the burning of a significant portion of the transaction fees. We prove that this new mechanism earns an impressive report card: it satisfies the MMIC and OCA-proofness conditions, and is also dominant-strategy incentive compatible (DSIC) except when there is a sudden demand spike. We also introduce an alternative design, the "tipless mechanism," which offers an incomparable slate of incentive-compatibility guarantees -- it is MMIC and DSIC, and OCA-proof unless in the midst of a demand spike.

翻译：比特币和以太坊等区块链的需求远超供给，因此需要设计一种机制，从所有待处理交易中选择一部分"上链"。本文通过机制设计的视角研究区块链交易费用机制的设计问题。我们引入两种新的激励相容性概念，以捕捉区块链场景中的特定特性：一种（MMIC）防范追求利润最大化的矿工偏离行为，另一种（OCA-proofness）防范矿工与用户之间的链下合谋。这项研究可立即应用于近期（2021年8月5日）以太坊交易费用机制的一项重大改革——基于名为"EIP-1559"的提案。历史上，以太坊的交易费用机制采用一级价格（按出价付费）拍卖。EIP-1559提出了一系列紧密耦合的变革，包括引入可变大小区块、依赖历史数据的保留价格，以及销毁大部分交易费用。我们证明这一新机制获得了令人瞩目的评价：它满足MMIC和OCA-proofness条件，且除突发需求激增外，还满足占优策略激励相容性（DSIC）。同时，我们引入了一种替代设计——"无小费机制"（tipless mechanism），其提供了一套不可比拟的激励相容性保证：该机制满足MMIC和DSIC，且除需求激增期间外满足OCA-proofness。