Post-Quantum's Classic McEliece Algorithm Achieves Global ISO Standardization to Protect Against Quantum Cyber Attacks

Post-Quantum’s Classic McEliece algorithm has achieved global standardization by the International Organization for Standardization (ISO). The move amends the existing ISO/IEC 18033-2 encryption standard and establishes Classic McEliece as a trusted tool for protecting data and communications against future quantum-powered cyber attacks. Completed in June 2026, the standard was developed by an international team that includes researchers from the Okinawa Institute of Science and Technology (OIST) and Eindhoven University of Technology. The algorithm is already running in real-world systems and is expected to see wider use following formal ISO recognition.

Proven Security Track Record

Classic McEliece builds on a public-key system first proposed by Robert J. McEliece in 1978. It uses a different mathematical foundation from the encryption methods that dominate today’s internet, giving it strong resistance to both conventional and quantum attacks. After nearly five decades of continuous study by cryptographers, its security profile is among the best understood of any post-quantum candidate. Key contributors including Daniel J. Bernstein, Tanja Lange, and Carlos Cid helped refine the design, write the formal specifications, and guide it through the ISO process. The resulting standard keeps public keys relatively large while producing very small encrypted messages, a practical advantage for many network applications.

Path to Wider Commercial Use

ISO approval removes a major barrier for companies and governments that require internationally recognized standards before deploying new security tools. Classic McEliece is already embedded in several production systems, including secure network products and hardware modules. Its compact encrypted messages make it well suited for bandwidth-sensitive environments such as virtual private networks and high-speed transport. Post-Quantum, which has long championed the algorithm, now has a formal international endorsement that should accelerate adoption across critical infrastructure, defense, and enterprise markets. National security agencies have previously endorsed larger versions of the same family for long-term data protection, and many countries are targeting full post-quantum migration by 2035. The ISO decision also creates a clear reference point that can support future alignment with other global standards bodies.

Bottom Line

Classic McEliece’s ISO standardization delivers a mature, ready-to-use option for quantum-resistant data protection.

Find out more here.

—

Further articles, reports, and the latest quantum computing news may be found at The Qubit Report.