Post-Quantum Cryptography: Why Your Encryption Is Already Obsolete

NIST has formally published its first set of post-quantum cryptography standards, giving organizations a roadmap for migrating away from encryption algorithms that quantum computers will eventually break. The standards — ML-KEM for key establishment and ML-DSA and SLH-DSA for digital signatures — replace RSA and elliptic-curve cryptography in systems that must remain secure for decades.

The Quantum Threat

Quantum computers powerful enough to break current public-key encryption do not yet exist, but security agencies warn against complacency. Adversaries are already harvesting encrypted data today with the intent of decrypting it once quantum computers become available — a strategy known as "harvest now, decrypt later." Any sensitive data with a long shelf life is at risk.

"The transition to post-quantum cryptography is the largest migration in the history of cybersecurity," said Lily Chen, NIST mathematician and leader of the post-quantum standardization effort. "It affects every device, every protocol, and every organization that uses encryption."

What Needs to Change

Migrating to post-quantum algorithms is not a simple software update. Organizations must inventory every system that uses cryptography, assess which data is most sensitive, and replace vulnerable algorithms in a coordinated global effort. Key areas include:

• Web browsers and TLS: Already beginning to support hybrid post-quantum key exchange
• VPNs and network equipment: Requires firmware and hardware upgrades
• Code signing: Software supply chains must adopt quantum-resistant signatures
• Financial systems: Payment networks and banking infrastructure need long-term protection

The Timeline Challenge

Experts estimate that a full cryptographic migration will take 10-15 years, yet some intelligence agencies believe cryptographically relevant quantum computers could arrive within that window. Organizations handling classified information, critical infrastructure, or long-term financial records are being urged to begin migration immediately.

For most companies, the first step is discovery: understanding where cryptography is used across their environment. The organizations that start early will have a manageable transition. Those that wait may face a rushed and risky upgrade under the threat of a working quantum computer.