Real-World Cryptography

14 Post-quantum cryptography

This chapter covers

• Quantum computers and their impact on cryptography
• Post-quantum cryptography to defend against quantum computers
• The post-quantum algorithms of today and tomorrow

“Quantum computers can break cryptography,” implied Peter Shor, a professor of mathematics at MIT. It was 1994, and Shor had just come up with a new algorithm. His discovery unlocked efficient factoring of integers, destroying cryptographic algorithms like RSA if quantum computers ever were to become a reality. At the time, the quantum computer was just a theory, a concept of a new class of computer based on quantum physics. The idea remained to be proven. In mid-2015, the National Security Agency (NSA) took everybody by surprise ...