LEDAkem: a post-quantum key encapsulation mechanism based on QC-LDPC codes. (English) Zbl 1425.94046

Lange, Tanja (ed.) et al., Post-quantum cryptography. 9th international conference, PQCrypto 2018, Fort Lauderdale, FL, USA, April 9–11, 2018. Proceedings. Cham: Springer. Lect. Notes Comput. Sci. 10786, 3-24 (2018).
Summary: This work presents a new code-based key encapsulation mechanism (KEM) called LEDAkem. It is built on the Niederreiter cryptosystem and relies on quasi-cyclic low-density parity-check codes as secret codes, providing high decoding speeds and compact keypairs. LEDAkem uses ephemeral keys to foil known statistical attacks, and takes advantage of a new decoding algorithm that provides faster decoding than the classical bit-flipping decoder commonly adopted in this kind of systems. The main attacks against LEDAkem are investigated, taking into account quantum speedups. Some instances of LEDAkem are designed to achieve different security levels against classical and quantum computers. Some performance figures obtained through an efficient C99 implementation of LEDAkem are provided.
For the entire collection see [Zbl 1387.94005].


94A60 Cryptography
81P94 Quantum cryptography (quantum-theoretic aspects)


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