Cryptology ePrint Archive: Report 2019/730

PQDH: A Quantum-Safe Replacement for Diffie-Hellman based on SIDH

Vladimir Soukharev and Basil Hess

Abstract: We present a post-quantum key agreement scheme that does not require distinguishing between the initiator and the responder. This scheme is based on elliptic curve isogenies and can be viewed as a variant of the well-known SIDH protocol. Then, we present an efficient countermeasure against a side-channel attack that applies to both static and ephemeral versions of SIDH and our scheme. Finally, we show how to obtain an isogeny-based password-authenticated key exchange protocol based on our scheme by applying a construction based on SIDH. Security and computational complexities summaries are also presented.

Category / Keywords: public-key cryptography / isogenies, key agreement, side-channel attack, countermeasure, password-authenticated key exchange, post-quantum cryptography, elliptic curves

Date: received 19 Jun 2019, last revised 18 Jul 2019

Contact author: Vladimir Soukharev at infosecglobal com,Basil Hess@infosecglobal com