How Does a CEX Ensure Fair Transaction Ordering without a Public Mempool?

A Centralized Exchange (CEX) ensures fair transaction ordering using a private, centralized matching engine that processes orders based on strict, predefined rules. The primary rule is typically price-time priority: the best price order is executed first, and if prices are equal, the order submitted earliest is executed first.

This internal, sequential processing eliminates the opportunity for external actors to pay higher fees to jump the queue, which is the mechanism of front-running on public blockchains.

How Do CEXs Ensure Fair Transaction Execution without Mempool Transparency?
How Does an Off-Chain Matching Engine Work on a CEX?
Define “Latency Arbitrage” and How It Is Related to the Speed of a Matching Engine
What Is the Role of an Exchange’s Matching Engine in Ensuring Market Fairness?
How Do High-Frequency Trading (HFT) Firms Attempt to Gain an Advantage despite the Price-Time Priority Rule?
Can a Centralized Exchange (CEX) Environment Be Exploited by a Sandwich Attack?
What Is a ‘Stop-Market’ Order’s Priority in the Order Matching Engine?
What Is the Primary Function of a Matching Engine in a Crypto Exchange and How Can Its Design Prevent Front-Running?

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