Cryptosystems

Low-dEnsity parity-check coDe-bAsed cryptographic systems

A suite of code-based key-encapsulation and public-key encryption schemes built on quasi-cyclic low- and moderate-density parity-check (QC-LDPC / QC-MDPC) codes — a compact-key evolution of the McEliece cryptosystem. It grew out of the group's research and was admitted to the second round of NIST's first post-quantum standardization process.

Based on

Decoding of QC-LDPC / QC-MDPC codes

NIST

NIST PQC standardization — Round 2

Codes and Restricted Objects Signature Scheme

A code-based digital-signature scheme whose security rests on the restricted syndrome decoding problem. Built from zero-knowledge protocols, CROSS aims at fast operations and small keys, and is a second-round candidate in NIST's additional call for post-quantum signatures.

Based on

Restricted syndrome decoding (R-SDP)

NIST

NIST additional signatures call — Round 2

Linear Equivalence Signature Scheme

A code-based digital-signature scheme built on the hardness of deciding linear equivalence between codes. LESS turns the code-equivalence problem into a zero-knowledge identification scheme and, via Fiat–Shamir, into a signature. It is a second-round candidate in NIST's additional call for post-quantum signatures.

Based on

Linear code equivalence

NIST

NIST additional signatures call — Round 2

Linear Equivalence Action Threshold Signature

A threshold digital-signature scheme based on the linear equivalence problem between codes, derived from LESS. It distributes signing across multiple parties so that a quorum is required to produce a signature.

Based on

Linear code equivalence

NIST

Threshold variant of the NIST candidate LESS