Efficient and reliable post-quantum authentication

Abstract

In this paper we propose a new lightweight authentication protocol which is efficient, reliable and, properly instantiated, suitable for the post-quantum world. It is a two-level protocol, which supports unbounded message transmission. It can be useful in several settings, from the standard sender-receiver setting, to unreliable multicast and broadcast communication in networks with resource-constrained devices. The key ideas underlying our design are mainly three: the hash-chaining method, some techniques used in MAC-based authentication protocols for multicast communication, and the use of the Guy Fawkes signatures. To our knowledge, our protocol is the first one that solves the unbounded number of message transmission issue in unreliable settings. It does not lose efficiency and introduces only a constant-size overhead in message transmission, compared to solutions assuming a bounded number of message transmissions. We rigorously model the adversarial setting and show that our protocol satisfies the definition, leveraging on standard assumptions. Apart from the technical contribution, along the line, we also point out the relevance of ideas and techniques developed in the past in the area of efficient authentication, in order to provide new authentication schemes, ready for the post-quantum world.