Quantum Exchange

Arash Atashpendar, Guru-Vamsi Policharla, Peter Browne Rønne +1 more

We revisit the notion of deniability in quantum key exchange (QKE), a topic that remains largely unexplored. In the only work on this subject by Donald Beaver, it is argued that QKE is not necessarily deniable due to an eavesdropping attack that limits key equivocation. We provide more insight into the nature of this attack and how it extends to other constructions such as QKE obtained from uncloneable encryption. We then adopt the framework for quantum authenticated key exchange, developed by Mosca et al., and extend it to introduce the notion of coercer-deniable QKE, formalized in terms of the indistinguishability of real and fake coercer views. Next, we apply results from a recent work by Arrazola and Scarani on covert quantum communication to establish a connection between covert QKE and deniability. We propose DC-QKE, a simple deniable covert QKE protocol, and prove its deniability via a reduction to the security of covert QKE. Finally, we consider how entanglement distillation can be used to enable information-theoretically deniable protocols for QKE and tasks beyond key exchange.

Charlotte D. Shelton

Amber Jenkins

Scott R. Fluhrer, Cen Jung Tjhai, Óscar García-Morchón +3 more

This document describes how to extend Internet Key Exchange Protocol Version 2 (IKEv2) so that the shared secret exchanged between peers has resistance against quantum computer attacks. The basic idea is to exchange one or more post-quantum key exchange payloads in conjunction with the existing (Elliptic Curve) Diffie-Hellman payload.

Michael McGregor, Michael Haney

Quantum cryptography and key exchange is an important and challenging topic for cybersecurity and information assurance students, and one that is difficult to teach without an appropriate demonstration platform. In this paper, we describe the background of quantum key exchange (QKE) theory, modern implementations of QKE, and the role it plays in classical, symmetric key cryptography. We present a QKE simulator that can be used by educators to aid in the teaching of quantum key exchange concepts and processes. The simulator provides a hands-on learning mechanism with which the participants interact. It is designed to be engaging and practical for students to use by supporting the ability to walk through phases of quantum key exchange, pausing at each step, to facilitate discussion and comprehension of this complex security topic.