Efficient and probably secure key agreement

Shimpei Yasukawa, Hisato Iwai, Hideichi Sasaoka

As a countermeasure for eavesdroppers in wireless communication, a secret key agreement scheme using a variable directional antenna named ESPAR antenna was developed. In this paper, we describe an improved key generation method using multi-level quantization and parity check in the secret key agreement scheme. It enhances key agreement probability in legitimate parties efficiently without reducing the security. There was a trade-off between the key agreement probability and the security. Simulation result shows that the proposed method realizes higher security than the conventional one in the key agreement system using ESPAR antenna.

Nikolaos Alexandris, Mike V. D. Burmester, Vasilios Chrissikopoulos +1 more

XU Chun-xiang

A few of certificateless key agreement schemes have been proposed in recent years,all of them need pairing operations,what's more,most of them are vulnerable to the key compromise impersonation attack and resistance to leakage of ephemeral keys.The provably secure certificateless key agreement protocol was proposed by Lippold in 2009,but their protocol suffered from computation burden.In order to solve the above-mentioned problem,this paper proposed a new pairing-free certificateless two party key agreement scheme (CL-KA) and presened its security properties.The new scheme was secure as long as each party had at least one uncompromised secret.Thus,the new scheme was secure even if the key generation centre learned the ephemeral secrets of both parties.The new scheme achieves efficiency in computational cost when compared with Lippold's protocol.

孝也 栃窪

Wenhao Liu, Chunxiang Xu, Jian Feng Xu

Certificateless cryptography aims at combining the advantages of identity based and public key cryptography in order to avoid the key escrow problem inherent in the identity based cryptography and cumbersome certificate management in the traditional public key infrastructure. The provably secure certificateless key agreement protocol is proposed by Lippold et al. in 2009, but their protocol suffers from computation burden. Owing to the above-mentioned situations, a new certificateless two party key agreement protocol (CL-KA) is proposed and the security attributes are analyzed in the extended Canetti-Krawzcyk(eCK) security model. Our protocol only requires each entity to compute two pairings, up to now, it turns out to be the most efficient one of all the previously known security CL-KA schemes.

Jin Li-jie, Chunxiang Xu