Post-Quantum Cryptography

Post-quantum cryptography (PQC) is the next generation of encryption algorithms designed to secure critical infrastructure, broadband networks, and sensitive data against attacks from both classical computers and future quantum computers. Current widely-deployed encryption methods—including RSA and elliptic curve cryptography protecting most internet communications, financial transactions, and government systems—rely on mathematical problems that sufficiently powerful quantum computers could solve rapidly using Shor's algorithm, potentially compromising decades of encrypted data.

In August 2024, the National Institute of Standards and Technology (NIST) released the first three finalized post-quantum cryptography standards (ML-KEM, ML-DSA, and SLH-DSA), and in March 2025 selected the HQC algorithm as a backup key encapsulation mechanism. The FY 2027 R&D memorandum explicitly prioritizes post-quantum cryptography readiness as essential to national cybersecurity resilience.

For BEAD-funded broadband infrastructure with operational lifespans exceeding 20 years, quantum-resistant network design is a present-day critical infrastructure requirement. Networks deployed today will remain operational when cryptographically relevant quantum computers emerge, necessitating cryptographic agility—the architectural capability to transition encryption protocols without costly hardware replacement across funded service areas.