For the network architects and engineers who run global WANs, post-quantum cryptography is now a deployment decision. This note covers NIST's finalized algorithms, current SD-WAN vendor readiness, performance versus classical cryptography, hybrid implementation guidance and a phased, WAN-first migration strategy.

Core routing has the hardest post-quantum migration in networking. This note gives network architects and infrastructure leaders a clear read on where Cisco, HPE Networking, and Nokia stand on PQC today, plus the near-term actions that protect backbone traffic now.