Improving the single-assumption authenticated Diffie-Hellman key agreement protocols

Abstract

In 2005, Harn et al. proposed three authenticated Diffie-Hellman key-agreement protocols, each of which is based on one cryptographic assumption. In particular, the first protocol is based on a discrete logarithm, the second on an elliptic curve and the third on RSA factoring. However, the current paper demonstrates that Harn et al.'s protocols do not provide perfect forward secrecy and key freshness which are two of the standard security attributes that key exchange protocols should have. Furthermore, we proposes improvements of the protocols such that they provide these security attributes. © Springer-Verlag Berlin Heidelberg 2007.