SPEEDEX is a decentralized exchange (DEX) that lets participants securely trade assets without giving any single party undue control over the market. SPEEDEX offers several advantages over prior DEXes. It achieves high throughput -- over 200,000 transactions per second on 48-core servers, even with tens of millions of open offers. SPEEDEX runs entirely within a Layer-1 blockchain, and thus achieves its scalability without fragmenting market liquidity between multiple blockchains or rollups. It eliminates internal arbitrage opportunities, so that a direct trade from asset $\mathcal{A}$ to asset $\mathcal{B}$ always receives as good a price as trading through some third asset such as USD. Finally, it prevents certain front-running attacks that would otherwise increase the effective bid-ask spread for small traders. SPEEDEX's key design insight is its use of an Arrow-Debreu exchange market structure that fixes the valuation of assets for all trades in a given block of transactions. We construct an algorithm, which is both asymptotically efficient and empirically practical, that computes these valuations while exactly preserving a DEX's financial correctness constraints. Not only does this market structure provide fairness across trades, but it also makes trade operations commutative and hence efficiently parallelizable. SPEEDEX is prototyped but not yet merged within the Stellar blockchain, one of the largest Layer-1 blockchains.

翻译：SPEEDEX是一种去中心化交易所（DEX），允许参与者安全交易资产，同时防止任何单一实体过度控制市场。与先前DEX相比，SPEEDEX具有多项优势：它实现了高吞吐量——即使在拥有数千万笔公开挂单的情况下，在48核服务器上每秒可处理超过20万笔交易。SPEEDEX完全运行在Layer-1区块链内，因此其可扩展性无需跨多条区块链或Rollup分割市场流动性。它消除了内部套利机会，使得从资产$\mathcal{A}$直接交易到资产$\mathcal{B}$总能获得与通过美元等第三方资产交易同样优越的价格。此外，SPEEDEX能防止某些前置交易攻击，这类攻击本会增加小额交易者的有效买卖价差。SPEEDEX的关键设计思想在于采用Arrow-Debreu交换市场结构，该结构在给定交易区块中为所有交易固定资产估值。我们构建了一种既渐进高效又具有经验实用性的算法，能在精确保持DEX财务正确性约束的同时计算这些估值。这种市场结构不仅提供了跨交易的公平性，还使交易操作具有交换性，从而实现高效并行化。SPEEDEX的原型已在全球最大的Layer-1区块链之一——Stellar区块链中开发，但尚未合并。