Bitcoin Core outlined three goals for transaction relay in its June 6, 2025 joint statement: mining prediction, block propagation speed, and miner fee awareness

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According to the developers, transaction relay has three major goals. This includes predicting which transactions will be mined, which also serves to prevent denial-of-service (DoS) attacks. In DoS attacks, miscreants flood the network with spam transactions, overwhelming the network and preventing it from processing transaction requests from legitimate users.

The goals of transaction relay include: predicting what transactions will be mined (for example for fee estimation or fee bumping, but it is also the basis for many DoS protection strategies inside of node software); speeding up block propagation for the transactions we expect to be mined. Reduced latency helps prevent large miners from gaining unfair advantages; helping miners learn about fee-paying transactions (so they do not need to rely on out-of-band transaction submission schemes that undermine mining decentralization).