Ouroboros: A Simple, Secure and Efficient Key Exchange Protocol Based on Coding Theory

Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10346)


We introduce Ouroboros (The Ouroboros symbol is an ancient symbol which represents the notion of cyclicity in many civilizations), a new Key Exchange protocol based on coding theory. The protocol gathers the best properties of the recent MDPC-McEliece and HQC protocols for the Hamming metric: simplicity of decoding and security reduction, based on a double cyclic structure. This yields a simple, secure and efficient approach for key exchange. We obtain the same type of parameters (and almost the same simple decoding) as for MDPC-McEliece, but with a security reduction to decoding random quasi-cyclic codes in the Random Oracle Model.


Post-quantum cryptography Coding theory Key exchange 


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© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.University of LimogesLimogesFrance
  2. 2.University of BordeauxBordeauxFrance

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