BNB Chain has completed a test of post-quantum cryptography on its BSC network, but the results show a clear trade-off between security and performance. The BNB Chain team released its BSC Post-Quantum Cryptography Migration Report on May 14, detailing how the network handled new quantum-resistant signatures. They tested ML-DSA-44 for transaction signatures and used pqSTARK for consensus vote aggregation.
The test showed that the system can work with existing BSC infrastructure. It remains compatible with current addresses, RPCs, SDKs, wallets, and transaction flows. This means users and developers would not need to change basic account formats if the design ever goes into production. BNB Chain said in the report that “post-quantum readiness is achievable on BSC today,” but they also admitted that data growth and network limits remain the main trade-offs. The team also noted that quantum computers are “not yet at a stage” where they can break current cryptographic systems in real-world scenarios.
BSC TPS drops as signature size jumps
The biggest issue came from data size. BNB Chain said that transaction signatures jumped from 65 bytes to 2,420 bytes after switching from ECDSA to ML-DSA-44. The full transaction size grew from 110 bytes to around 2.5 KB. That extra load cut performance noticeably during testing. The report said block size increased to about 2 MB, while throughput dropped by roughly 40% to 50% in tests. In cross-region scenarios, TPS dropped by about 40%, showing that network propagation becomes harder when blocks carry more data. The report added that finality stayed at two slots in median cases. The wider gap in slower cases came from larger blocks moving across regions, not from a failure in the consensus design itself.
pqSTARK aggregation helps validator load
Consensus vote aggregation performed better than the transaction layer. BNB Chain said that pqSTARK aggregation delivered about 43:1 compression, which helped keep validator overhead manageable during the test. However, the upgrade did not cover every part of BSC’s cryptographic system. The report noted that peer-to-peer handshakes and KZG commitments remain outside the current migration. P2P migration would need ML-KEM, while replacing KZG would require coordination with the broader Ethereum ecosystem. The test shows that BSC can move toward quantum-resistant security, but the scaling work needed is real and probably not trivial.
Speed roadmap faces new trade-off
This post-quantum test adds a fresh layer to BNB Chain’s wider performance roadmap. Related reports indicate that BNB Chain has been targeting sub-150 millisecond finality and more than 20,000 TPS for complex transactions by 2026. That speed goal now has to coexist with quantum-resistant security work. The latest test shows that BSC can adopt ML-DSA-44 and pqSTARK, but larger signatures could make those high-throughput targets harder to reach without better data handling and network scaling. The path forward seems to involve a balancing act between future-proofing against quantum threats and maintaining the performance that users expect today.
