Serious Cryptography, 2nd Edition

14 QUANTUM AND POST-QUANTUM

In this chapter, we’ll examine the future of cryptography over a time horizon of, say, a century or more—one in which quantum computers may exist. Quantum computers leverage phenomena from quantum physics to run different kinds of algorithms than we’re used to. While large quantum computers don’t exist yet, they have the potential to break RSA, Diffie–Hellman, and elliptic curve cryptography—all the public-key crypto deployed or standardized as of this writing.

To ensure against the quantum computing risk, cryptography researchers have developed alternative public-key post-quantum algorithms. In 2015, the NSA ...