IETF RFC 9958
[ACTIVE]
Post-Quantum Cryptography for Engineers
Metadata
- Publisher
- IETF
- Doc Type
- Informational
- Pages
- 42
- Abstract
- The advent of a cryptographically relevant quantum computer (CRQC) would render state-of-the-art, traditional public key algorithms deployed today obsolete, as the mathematical assumptions underpinning their security would no longer hold. To address this, protocols and infrastructure must transition to post-quantum algorithms, which are designed to resist both traditional and quantum attacks. This document explains why engineers need to be aware of and understand post-quantum cryptography (PQC), and it details the impact of CRQCs on existing systems and the challenges involved in transitioning to post-quantum algorithms. Unlike previous cryptographic updates, this shift may require significant protocol redesign due to the unique properties of post-quantum algorithms.
- Publication Date
- 2026-06-01
- Status Note
- Informational
- DOI
10.17487/RFC9958- Link
- https://doi.org/10.17487/RFC9958
- Author(s)
- Aritra BanerjeeTirumaleswar Reddy.KDimitrios SchoinianakisTim HollebeekMike Ounsworth
- Keyword(s)
- Post-quantum Cryptography
Latest version of IETF RFC 9958
Document Versions — IETF RFC 9958
-
▶ IETF RFC 9958 (2026-06-01)THIS DOC [ACTIVE] [LATEST VERSION]
Normative Reference(s)
- 10.1145-237814.237866 — GROVER EXTERNAL
- 10.1145-359340.359342 — RSA EXTERNAL
- NIST.FIPS.203 — ML-KEM EXTERNAL
- NIST.FIPS.204 — ML-DSA EXTERNAL
- NIST.FIPS.205 — SLH-DSA EXTERNAL
- "NTRU", <https://ntru.org/index.shtml>. EXTERNAL
- "Classic McEliece", <https://classic.mceliece.org/>. EXTERNAL
- "FALCON: Fast Fourier lattice-based compact signatures over NTRU", <https://falcon-sign.info/>. EXTERNAL
- "FrodoKEM", <https://frodokem.org/>. EXTERNAL
- Shor, P., "Polynomial-Time Algorithms for Prime Factorization and Discrete Logarithms on a Quantum Computer", arXiv:quant-ph/9508027v2, 25 January 1996, <https://arxiv.org/pdf/quant-ph/9508027>. EXTERNAL
- IETF RFC 4034 [Active*]
- IETF RFC 6090 [Active*]
- RFC8235 — RFC8235 EXTERNAL
- IETF RFC 8391 [Active*]
- IETF RFC 8446 [Superseded*]
- RFC8554 — RFC8554 EXTERNAL
- RFC9180 — RFC9180 EXTERNAL
- IETF RFC 9242 [Active*]
- IETF RFC 9370 [Active*]
- RFC9881 — RFC9881 EXTERNAL
Bibliographic Reference(s)
- 10.1007-978-3-030-17259-6_19 — LattFail1 EXTERNAL
- 10.1007-978-3-030-45727-3_1 — LattFail2 EXTERNAL
- 10.1007-s13389-023-00315-3 — SaberSide EXTERNAL
- 10.1103-PhysRevA.60.2746 — Grover-Search EXTERNAL
- 10.1109-OJCS.2022.3198073 — Mitigate2 EXTERNAL
- 10.1137-0217017 — GMR88 EXTERNAL
- GITHUB.open-quantum-safe.liboqs — LIBOQS EXTERNAL
- IETF.draft-bonnell-lamps-chameleon-certs-07 — I-D.bonnell-lamps-chameleon-certs EXTERNAL
- IETF.draft-connolly-cfrg-xwing-kem-10 — I-D.connolly-cfrg-xwing-kem EXTERNAL
- IETF.draft-ietf-hpke-pq-04 — I-D.ietf-hpke-pq EXTERNAL
- IETF.draft-ietf-lamps-pq-composite-sigs-19 — I-D.ietf-lamps-pq-composite-sigs EXTERNAL
- IETF.draft-ietf-mls-combiner-02 — I-D.ietf-mls-combiner EXTERNAL
- IETF.draft-ietf-pquip-hybrid-signature-spectrums-07 — I-D.ietf-pquip-hybrid-signature-spectrums EXTERNAL
- IETF.draft-ietf-pquip-pqc-hsm-constrained-05 — I-D.ietf-pquip-pqc-hsm-constrained EXTERNAL
- IETF.draft-ietf-tls-hybrid-design-16 — I-D.ietf-tls-hybrid-design EXTERNAL
- IETF.draft-irtf-cfrg-bbs-signatures-10 — I-D.irtf-cfrg-bbs-signatures EXTERNAL
- IETF.draft-irtf-cfrg-hybrid-kems-11 — I-D.irtf-cfrg-hybrid-kems EXTERNAL
- IETF.draft-ounsworth-cfrg-kem-combiners-05 — I-D.ounsworth-cfrg-kem-combiners EXTERNAL
- ISBN.9781718503847 — Serious-Crypt EXTERNAL
- NIST.SP.800-56Cr2 — SP-800-56C EXTERNAL
- IETF, "Post-Quantum Use In Protocols (pquip)", <https://datatracker.ietf.org/group/pquip/documents/>. EXTERNAL
- Mosca, M. and M. Piani, "Quantum Threat Timeline Report 2020", Global Risk Institute, 27 January 2021, <https://globalriskinstitute.org/publications/quantum-threat-timeline-report-2020/>. EXTERNAL
- NIST, "PQC - API notes", <https://csrc.nist.gov/CSRC/media/Projects/Post-Quantum-Cryptography/documents/example-files/api-notes.pdf>. EXTERNAL
- Beauregard, S., "Circuit for Shor's algorithm using 2n+3 qubits", arXiv:quant-ph/0205095v3, 21 February 2003, <https://arxiv.org/pdf/quant-ph/0205095.pdf>. EXTERNAL
- Westerbaan, B., "NIST's pleasant post-quantum surprise", Cloudflare Blog, 8 July 2022, <https://blog.cloudflare.com/nist-post-quantum-surprise/>. EXTERNAL
- Chalkias, K., Brown, J., Hearn, M., Lillehagen, T., Nitto, I., and T. Schroeter, "Blockchained Post-Quantum Signatures", Cryptology ePrint Archive, Paper 2018/658, <https://eprint.iacr.org/2018/658>. EXTERNAL
- Xu, C., Erata, F., and J. Szefer, "Exploration of Quantum Computer Power Side-Channels", arXiv:2304.03315v2, 9 May 2023, <https://arxiv.org/pdf/2304.03315>. EXTERNAL
- NIST, "Post-Quantum Cryptography: Additional Digital Signature Schemes", <https://csrc.nist.gov/Projects/pqc-dig-sig/standardization>. EXTERNAL
- Ngo, K., Wang, R., Dubrova, E., and N. Paulsrud, "Side-Channel Attacks on Lattice-Based KEMs Are Not Prevented by Higher-Order Masking", Cryptology ePrint Archive, Paper 2022/919, 2022, <https://eprint.iacr.org/2022/919>. EXTERNAL
- NIST, "Post-Quantum Cryptography Standardization", <https://csrc.nist.gov/projects/post-quantum-cryptography/post-quantum-cryptography-standardization>. EXTERNAL
- Ravi, P., Roy, S. S., Chattopadhyay, A., and S. Bhasin, "Generic Side-channel attacks on CCA-secure lattice-based PKE and KEM schemes", Cryptology ePrint Archive, Paper 2019/948, 2019, <https://eprint.iacr.org/2019/948>. EXTERNAL
- "Open Quantum Safe Project", <https://openquantumsafe.org/>. EXTERNAL
- "BIKE", <https://bikesuite.org/>. EXTERNAL
- Azouaoui, M., Kuzovkova, Y., Schneider, T., and C. V. Vredendaal, "Post-Quantum Authenticated Encryption against Chosen-Ciphertext Side-Channel Attacks", Cryptology ePrint Archive, Paper 2022/916, 2022, <https://eprint.iacr.org/2022/916>. EXTERNAL
- NIST, "NIST Releases First 3 Finalized Post-Quantum Encryption Standards", 13 August 2024, <https://www.nist.gov/news-events/news/2024/08/nist-releases-first-3-finalized-post-quantum-encryption-standards>. EXTERNAL
- Hoffmann, C., Libert, B., Momin, C., Peters, T., and F. Standaert, "POLKA: Towards Leakage-Resistant Post-Quantum CCA-Secure Public Key Encryption", Cryptology ePrint Archive, Paper 2022/873, 2022, <https://eprint.iacr.org/2022/873>. EXTERNAL
- BSI, "Quantum-safe cryptography - fundamentals, current developments and recommendations", 18 May 2022, <https://www.bsi.bund.de/SharedDocs/Downloads/EN/BSI/Publications/Brochure/quantum-safe-cryptography.html?nn=916626>. EXTERNAL
- Bernstein, D. J., Heninger, N., Lou, P., and L. Valenta, "Post-quantum RSA", 19 April 2017, <https://cr.yp.to/papers/pqrsa-20170419.pdf>. EXTERNAL
- QuintessenceLabs, "Breaking RSA Encryption - an Update on the State-of-the-Art", 13 June 2019, <https://www.quintessencelabs.com/blog/breaking-rsa-encryption-update-state-art>. EXTERNAL
- ANSSI, "ANSSI views on the Post-Quantum Cryptography transition (2023 follow up)", 21 December 2023, <https://cyber.gouv.fr/sites/default/files/document/follow_up_position_paper_on_post_quantum_cryptography.pdf>. EXTERNAL
- Cramer, R. and V. Shoup, "Design and Analysis of Practical Public-Key Encryption Schemes Secure against Adaptive Chosen Ciphertext Attack", Cryptology ePrint Archive, Paper 2001/108, 2001, <https://eprint.iacr.org/2001/108>. EXTERNAL
- Cremers, C., Dax, A., and N. Medinger, "Keeping Up with the KEMs: Stronger Security Notions for KEMs and automated analysis of KEM-based protocols", Cryptology ePrint Archive, Paper 2023/1933, 2023, <https://eprint.iacr.org/2023/1933>. EXTERNAL
- Lyubashevsky, V., "Fiat-Shamir With Aborts: Applications to Lattice and Factoring-Based Signatures", ASIACRYPT 2009, <https://www.iacr.org/archive/asiacrypt2009/59120596/59120596.pdf>. EXTERNAL
- Jaques, S., "Landscape of Quantum Computing", <https://sam-jaques.appspot.com/quantum_landscape_2024>. EXTERNAL
- Bellare, M., Hofheinz, D., and E. Kiltz, "Subtleties in the Definition of IND-CCA: When and How Should Challenge-Decryption be Disallowed?", Cryptology ePrint Archive, Paper 2009/418, 2009, <https://eprint.iacr.org/2009/418>. EXTERNAL
- "HQC", <http://pqc-hqc.org/>. EXTERNAL
- Gidney, C. and M. Ekera, "How to factor 2048 bit RSA integers in 8 hours using 20 million noisy qubits", arXiv:1905.09749v3, 13 April 2021, <https://arxiv.org/abs/1905.09749>. EXTERNAL
- Hoffman, P., "Quantum Computing and the DNS", ICANN Office of the Chief Technology Officer, OCTO-031v2, 22 April 2024, <https://www.icann.org/octo-031-en.pdf>. EXTERNAL
- NSA, "Announcing the Commercial National Security Algorithm Suite 2.0", September 2022, <https://media.defense.gov/2025/May/30/2003728741/-1/-1/0/CSA_CNSA_2.0_ALGORITHMS.PDF>. EXTERNAL
- Newhouse, W., Souppaya, M., Barke, W., Brown, C., Kampanakis, P., Goodman, J., Prat, J., Larrieu, R., Gray, J., Ounsworth, M., Viana, C., Gong, H. L. V., Kwiatkowsk, K., Hu, A., Burns, R., Paquin, C., Gilbert, J., Scinta, G., Kim, E., and V. Krumme, "Migration to Post-Quantum Cryptography Quantum Readiness: Testing Draft Standards, Volume C: Quantum-Resistant Cryptography Technology Interoperability and Performance Report", Preliminary Draft, NIST SP 1800-38C, December 2023, <https://www.nccoe.nist.gov/sites/default/files/2023-12/pqc-migration-nist-sp-1800-38c-preliminary-draft.pdf>. EXTERNAL
- Ji, Y., Wang, R., Ngo, K., Dubrova, E., and L. Backlund, "A Side-Channel Attack on a Hardware Implementation of CRYSTALS-Kyber", Cryptology ePrint Archive, Paper 2022/1452, 2022, <https://eprint.iacr.org/2022/1452>. EXTERNAL
- PCI Security Standards Council, "Payment Card Industry Data Security Standard", PCI DSS: v4.0.1, <https://docs-prv.pcisecuritystandards.org/PCI%20DSS/Standard/PCI-DSS-v4_0_1.pdf>. EXTERNAL
- IETF RFC 5652 [Active*]
- RFC9528 — RFC9528 EXTERNAL
- RFC9763 — RFC9763 EXTERNAL
- RFC9794 — RFC9794 EXTERNAL
- RFC9814 — RFC9814 EXTERNAL
- RFC9941 — RFC9941 EXTERNAL
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IETF RFC 9958, Post-Quantum Cryptography for Engineers
doi: 10.17487/RFC9958
url: https://doi.org/10.17487/RFC9958
doi: 10.17487/RFC9958
url: https://doi.org/10.17487/RFC9958
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Referenced By
- IETF RFC 9852 [Active*]