Provably secure two-party authenticated key agreement protocol for post-quantum environments

Abstract

A two-party authenticated key agreement (2PAKA) protocol is a cryptographic tool employed widely to allow two users to generate a shared and fresh session key between them in each session over an insecure network. The authenticated version of a two-party key agreement protocol is popular because it can easily withstand the impersonation of the user. In the literature, many 2PAKA protocols have been put forward with the intractability assumptions of the discrete logarithm (DLP) problem and integer factorization problem (IFP). Some recent studies showed that the 2PAKA protocols based on these assumptions are insecure in post-quantum environments. To resolve this issue, we have designed a lattice-based 2PAKA (LB-2PAKA) protocol with the intractability of the ring-learning-with-errors (RLWE) problem. The proposed LB-2PAKA protocol is also analyzed in the random oracle model to measure provable security and to estimate the breaching time. To evaluate the performance, we used the LatticeCrypto Library and estimated the running time of our LB-2PAKA protocol. Besides, we analyzed the communication cost requirement of our LB-2PAKA protocol.