NIST Announces First Four Quantum-Resistant Cryptographic Algorithms

The U.S. Department of Commerce’s National Institute of
Standards and Technology (NIST) has chosen^[1]
the first set of quantum-resistant encryption algorithms that are
designed to “withstand the assault of a future quantum
computer.”

The post-quantum cryptography (PQC^[2]) technologies include
the CRYSTALS-Kyber^[3]
algorithm for general encryption, and CRYSTALS-Dilithium^[4], FALCON^[5], and SPHINCS+^[6] for digital
signatures.

“Three of the selected algorithms are based on a family of math
problems called structured lattices, while SPHINCS+ uses hash
functions,” NIST, which kicked off the standardization process in
January 2017, said^[7]
in a statement.

Cryptography, which underpins the security of information in
modern computer networks, derives its strength from the difficulty
of solving mathematical problems — e.g., factoring large composite
integers — using traditional computers.

Quantum computers, should they mature enough, pose a huge impact^[8]
on the current public-key algorithms, since what could take, say,
trillions of years^[9]
on a conventional computer to find the right key to decode a
message could merely take days^[10] or hours^[11], rendering them
susceptible to brute-force attacks.

“If large-scale quantum computers are ever built, they will be
able to break many of the public-key cryptosystems currently in
use,” the agency said. “This would seriously compromise the
confidentiality and integrity of digital communications on the
internet and elsewhere.”

Complicating matters further is a critical threat called
“hack now, decrypt later^[12]” wherein cyber
adversaries harvest sensitive encrypted data sent today in hopes of
breaking it in the future when quantum computing becomes
available.

The four quantum-resistant algorithms chosen by NIST are said to
rely on mathematical problems that are hard to solve on both
classical and quantum computers, thereby securing data against
cryptanalytic attacks.

The agency also plans to include four more algorithms before
finalizing the post-quantum cryptographic standard, a process
that’s expected to be completed in about two years.

That said, the U.S. Cybersecurity and Infrastructure Security
Agency (CISA), along with NIST, is “strongly” recommending^[13] organizations to start
preparing for the transition by following the Post-Quantum
Cryptography Roadmap^[14].