PQDH: A Quantum-Safe Replacement for Diffie-Hellman based on SIDH
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 shown in [16]. Security and computational complexities summaries are also presented.