BNB Chain's Quantum Defense Costs 40% of Throughput

BNB Chain has successfully tested its post-quantum cryptography migration on BSC, but at a significant cost to throughput. The network's Post-Quantum Cryptography Migration Report revealed that implementing quantum-resistant alternatives led to a 40% decrease in transactions per second.

The report compared the performance of two replacement cryptographic systems: ML-DSA-44 and pqSTARK aggregation for validator consensus votes. Cross-region tests showed that throughput dropped from 4,973 transactions per second to 2,997 under the new setup. Transaction sizes ballooned from roughly 110 bytes to about 2.5 KB, while signatures alone jumped from 65 bytes to 2,420 bytes.

Block sizes climbed from around 130 KB to nearly 2 MB at equivalent load. However, median finality latency held steady at two slots across all test scenarios. The pqSTARK proof system delivered a striking result by compressing six validator signatures totaling 14.5 KB into a single proof of about 340 bytes.

BNB Chain framed the work as a proof of concept rather than a production rollout, citing throughput constraints at the network and data layer as the central obstacle. The report also flagged P2P handshakes and KZG commitments as outside its current scope, requiring broader coordination with the Ethereum ecosystem.