Strongly Secure Authenticated Key Exchange Protocol Based on Computational Diffie-Hellman Problem.

Jooyoung Lee, Je Hong Park

Abstract. In this paper, we present a new authenticated key exchange(AKE) protocol and prove its security under the random oracle assumption and the computational Diffie-Hellman(CDH) assumption. In the extended Canetti-Krawczyk model, there has been no known AKE protocol based on the CDH assumption. Our protocol, called NAXOS+, is obtained by slightly modifying the NAXOS protocol proposed by LaMacchia, Lauter and Mityagin. We establish a formal security proof of NAXOS+ in the extended Canetti-Krawczyk model using as a main tool the trapdoor test presented by Cash, Kiltz and Shoup. Key words: authenticated key exchange, trapdoor test, computational Diffie-Hellman assumption, extended Canetti-Krawzcyk model 1

Jiaxin Pan, Chen Qian, Magnus Ringerud

Jiaxin Pan, Libin Wang

In this paper, we propose an authenticated key exchange (AKE) protocol under the computational Diffie-Hellman (CDH) assumption with respect to the strengthened eCK-security (seCK-security) of Sarr et al.. To date, many AKE protocols either are provably secure under a rather strong and non-standard assumption named as the gap Diffie-Hellman (GDH) assumption, or fall to practical attacks on the intermediate result leakage which can be captured by the seCK model. In order to remove the gap assumption and achieve stronger security requirements, we present the TMQV protocol using the twinning technique and the MQV key derivation method. With the help of trapdoor test theorem, TMQV is provably seCK-secure under the standard CDH assumption in the random oracle model. Compared with the related works, TMQV achieves not only stronger security but also higher implementation efficiency with weaker cryptographic assumptions.

Emmanuel Bresson, Olivier Chevassut, David Pointcheval

Daya Sagar Gupta, Gautam Biswas

Summary Key exchange protocols play an important role in securing the network communication over an insecure channel. In literature, a large number of key exchange schemes exist. The security of most of them is based on the Diffie‐Hellman (DH) problems over a group. But these types of DH problems are solvable in the presence of quantum computers. Thus, we require a non‐DH type key exchange scheme that resists to the quantum computers and new modern technologies. In this paper, 2 novel lattice‐based authenticated key exchange (LB‐AKE) protocols, (1) using a signature‐based authenticator and (2) using a signcryption‐based authenticator, are devised in Canetti‐Krawczyk proof model. The security of proposed protocols depends on the hardness of small integer solutions on the lattice. An extensive proof of security to our claim is given. The proposed AKEs characterize faster computation speed and resistance to the modern complex computers.

Timo Brecher, Emmanuel Bresson, Mark Manulis