Sebastien Rousseau

INFRA

Harvest now, decrypt later

The HNDL threat model — adversaries capturing encrypted traffic today to decrypt once quantum hardware is available.

6 articles

INFRASTRUCTURE & CRYPTOGRAPHY

Quantum Dawn for CIB: From KyberLib to a Quantum-Resilient Payments Stack

BIS Quantum Dawn and the G7 January 2026 PQC roadmap have moved post-quantum cryptography from research to board agenda. This piece extends KyberLib from a toolkit into an enterprise CIB transition programme — covering high-value rails, trade finance, custody, and the disclosures regulators are now asking for.

APPLIED AI

Post-Quantum Payments Infrastructure: Why Banks May Replace Rather Than Retrofit Legacy Rails

Harvest-now-decrypt-later turns today's TLS-protected payment messages into tomorrow's decrypted exposure. ML-KEM and ML-DSA are an order of magnitude larger than the RSA and ECC keys legacy rails were sized for — retrofit triggers fragmentation, latency, and HSM exhaustion. The 2026 architectural decision is whether to patch or replace before the regulatory clock runs out.