BNB Chain's Post-Quantum Upgrade Passes Tests — But Cuts TPS by 40%

BNB Chain has published its BSC Post-Quantum Cryptography Migration Report, confirming that BSC successfully tested a post-quantum upgrade using ML-DSA-44 for transaction signatures and pqSTARK for consensus vote aggregation. The design preserves backward compatibility with existing addresses, RPCs, SDKs, and wallets — a meaningful engineering constraint that was met.

The cost, however, is steep: signature size balloons from 65 bytes to 2,420 bytes, a 37x increase in data overhead, and cross-region transactions-per-second dropped by roughly 40% during testing. BNB Chain acknowledged that network and data-layer scaling remain the primary blockers before any production deployment can be considered.

The report positions this as a research milestone rather than an imminent rollout. The throughput hit is significant for a chain that competes on speed and low fees, and closing that gap will…