Nahid Yahyapoor - Department of Electrical Engineering, Khavaran Institute of Higher Education, Mashhad
Saeed Shaerbaf - Department of Electrical Engineering, International Universityof Imam Reza, Mashhad
Morteza Nikooghadam - Department of Computer Engineering, International Universityof Imam Reza, Mashhad

One of the most important cryptography protocols is the key agreement protocol in which used to build a shared secret key between two participants through an insecure channel. To increase the security and efficiency of these protocols, many researches have been performed. Recently, in 2012, Lee et al. proposed a key agreement protocol using smart cards and claimed their protocol is secure and efficient. However, He et al. proved that the Lee et al.'s protocol vulnerable to the privileged insider attack and the denial of service attack, and also the protocol cannot protect the user's true identity. We also point out the protocol requires timestamp information and the cost of card and reader makes this protocol costly. To overcome these weaknesses, we propose a key agreement protocol based on Chebyshev chaotic map without using smart card. Our protocol allows users to anonymously interact with the server. Moreover, analysis shows that the proposed protocol can successfully resist the current attacks.

Chebyshev chaotic map, Cryptography, Key agreement protocol, Logistic chaotic map, Session key