Cryptanalysis and improvement of an improved Identity-Based key exchange protocol

Abstract

A key exchange protocol is used to establish a common session key for two specified entities. In the past, the security attributes of a key exchange protocol have been identified clearly and specified. For the key exchange protocol proposed latterly, these security goals are required to achieve. In 2000, Saeednia proposed an identity-based key exchange protocol, which is a modification of Gunther’s protocol. Recently, Xie et al. proposed a slight modification of Saeednia’s protocol in order to reduce the computation cost. However, we find that their modification made no service of key compromise impersonation, one concrete security goal. Moreover, we modify Saeednia’s protocol in another way to reduce the computation cost and keep it resistant to the key compromise impersonation attack.