An Efficient Certificate-Based Authenticated Key Agreement Protocol without Bilinear Pairing

Abstract

An authenticated key agreement (AKA) protocol is extremely essential to secure communications over insecure public networks. It enables the communication parties to securely set up a shared session key in present of the malicious attackers. Certificate-based cryptography (CBC) is a novel public-key cryptographic primitive that has many attractive merits. It solves the certificate revocation problem in conventional public-key cryptography and the key-escrow problem in identity-based cryptography. Until now, four AKA protocols have been proposed in the setting of CBC. However, all of them adopt the costly bilinear pairings and are not suitable for the devices which have limited computing resources and battery power. Therefore, it is interesting and worthwhile to design a certificate-based AKA protocol without using the bilinear pairings. In this paper, we develop a pairing-free certificate-based AKA protocol. The proposed protocol is proven secure under the classic computational Diffie-Hellman assumption in the random oracle model. Compared with the previous pairing-based certificate-based AKA protocols, the proposed protocol enjoys obvious advantage in the computation efficiency.

Leakage-Resilient Certificate-Based Authenticated Key Exchange Protocol

“…Moreover, Lim et al [3] proposed a new CB-AKE protocol to improve the security. Latterly, many studies on CB-AKE protocols were published in the literatures [4], [5], [6].…”

“…They may employ the CSK to encrypt data and transmit the encrypted data to the other participant to ensure the confidentiality of the data. Until now, several CB-AKE protocols [3], [4], [5], [6] have been proposed. However, none of these protocols can resist side channel attacks [7], [8].…”

An Improved Certificate-less Authenticated Key Agreement Protocol

“…According to the comparison result, there is a threat of user key leakage and KCI attack caused by leaked temporary key in the literature [2,7]. Once the attacker steals any user's temporary private key, he can calculate user's private key by the correlation expression and implement KCI attacks.…”

“…But most of these protocols are based on bilinear pairs operation and the computational complexity is higher. Wenhao Liu et al [2] proposed a certificate-less two-party key agreement scheme without bilinear pairing and claimed that the scheme has a temporary key leak security. However, the analysis indicates that if the user's temporary key leaks, the user's master key expression ( + ) during the key agreement will be calculated.…”

“…However, the analysis indicates that if the user's temporary key leaks, the user's master key expression ( + ) during the key agreement will be calculated. In literature [2], user Alice calculated = /( + + ℎ)and sent to user Bob as the authentication parameter. Once Alice leaks temporary private key, the attacker can use the formula: + = − ℎ to calculate Alice's authentication private key ( + ) while s and h are public parameters.…”