BNB Chain’s Quantum-Safe Test Cuts Throughput by 40%

BNB Chain ran cross-region stress trials of quantum-safe cryptography and published a report this week. The new post-quantum signatures worked in the tests but increased signature size roughly 35-fold, and measured throughput fell from 4,973 transactions per second to 2,997 TPS.

Each transaction signature rose from 65 bytes to 2,420 bytes. Larger signatures increased block size and network load during heavy runs. Transactions that execute smart contracts experienced less slowdown because those transactions already include more data.

Validator voting used a compression method that bundles six votes into a single proof, shrinking combined vote size from about 14.5 kilobytes to roughly 340 bytes. That kept most block approvals fast; most blocks confirmed in about two slots during the trials. The slowest 1% of confirmations took up to 11 slots in cross-region runs, a delay the report linked to larger blocks taking longer to travel between regions.

The team wrote that the performance effects mean data and speed limits must be addressed before enabling the new cryptography for the full user base. The report outlined infrastructure upgrades intended to restore and expand capacity and listed objectives for the year, including raising throughput from 6,000 TPS to 20,000 TPS, reducing latency and improving finality.

The report noted additional components of the network still need quantum-safe upgrades and that some of that work will require coordination with the wider Ethereum developer community.

An excerpt in the report read: “Post-quantum readiness is achievable on BSC today, with data size growth and network constraints as the main trade-offs.”

The trial is part of an industry effort to prepare blockchains for the possibility that future quantum computers could break widely used cryptographic algorithms.