GoKawiilCryptographically relevant quantum computers, once available, are likely to greatly lessen the time and effort needed to break RSA, finite-field-based Diffie-Hellman (FFDH), or Elliptic Curve Cryptography (ECC) which are currently used in TLS. In 2016, the US National Institute of Standards and Technology (NIST) started a multi-year effort to standardize algorithms that will be "safe" once quantum computers are feasible [PQC]. Initial discussions in the IETF community happened around the same time [CFRGSLIDES].¶
In 2024, NIST released standards for [ML-KEM], [ML-DSA], and [SLH-DSA]. Many other countries and organizations are publishing their roadmaps, including the multi-national standards organization ETSI [ETSI].¶
While the industry was waiting for NIST to finish standardization, the IETF has had several efforts underway. A working group was formed in early 2023 to work on the use of Post-Quantum Cryptography (PQC) in IETF protocols [PQUIPWG]. Several other working groups, including TLS [TLSWG], are working on specifications to support hybrid algorithms and identifiers, for use during a transition from classic to a post-quantum world.¶
It is important to note that effort within the TLS Working Group is focused exclusively on TLS 1.3 or later. Put bluntly, PQC for TLS 1.2 will not be specified (see Section 4) at any time; anyone wishing to deploy PQC should expect to use TLS 1.3.¶