CRYPTO READING GROUP
HAMMING QUASI CYCLIC (HQC)

Organizers: Leonardo Colò, Seunghoon Lee, Bruno Sterner
When: Friday, 10:30a.m.
Where: MC5417
Goal: Understand the KEM/PKE HQC which was recently standardised by NIST.

PROGRAM

  1. Introduction to coding theory (Seunghoon Lee, Bruno Sterner - 15/05/2026)
      - Why was it proposed?
      - Basic definitions and properties.
      - Linear codes.
      - Reed-Solomon codes.
      > References: []
  2. Introduction to Code Based Cryptography (22/05/2026)
    • - Decoding problem.
      - McEliece framework.
      - Goppa codes instantiation (overview).
      > References: []
  3. Quasi-cyclic codes (29/05/2026)
    • - Definitions and properties.
      - MDPC-McEliece scheme.
      > References: []
  4. Information Set Decoding (05/06/2026)
    • - Decoding algorithms.
      - Prange’s algorithm.
      - Stern’s algorithm.
      > References: []
  5. Decoding for quasi-cyclic codes (12/06/2026)
    • - Syndrome decoding in the quasi-cyclic setting.
      - Generic ISD vs. Structure-aware decoding approaches.
      > References: []
  6. HQC KEM/PKE (19/06/2026)
    • - How doe it work?
      - Security analysis.
      > References: []
  7. HQC implementation and performance (26/06/2026)
    • - TBD
  8. Code-based signatures submitted to NIST on ramp (03/07/2026)
    • - CROSS or LESS

RESOURCES

  1. T. Debris-Alazard. Code-based Cryptography Lecture Notes, 2023
  2. HQC Team. Hamming Quasi-Cyclic (HQC). NIST Submission. 2025
  3. R. Misoczki, J.-P. Tillich, N. Sendrier, and P.S.L.M. Barreto. MDPC-McEliece: New McEliece Variants from Moderate Density Parity-Check Codes. 2013 IEEE International Symposium on Information Theory. 2013
  4. R. Roth. Introduction to Coding Theory. Cambridge University Press, 2006
  5. V. Weger, N. Gassner, and J. Rosenthal. A Survey on Code-based Cryptography. arXiv, 2024