Identity-based key agreement with unilateral identity privacy using pairings

Common key agreement protocols assume that both parties have some knowledge of each others identity or the identity is exchanged without protection. There are many real-world situations where this is either not possible or not desirable, e.g. mobile networks. This paper investigates the user identity privacy in the protocols employing identity-based primitives from pairings. By considering both security strength and computation efficiency, an identity-based protocol is proposed using pairing which preserves both user identity privacy and high efficiency. The proposed key exchange system is formally analysed to confirm its rigour.