Password authenticated key exchange based on RSA for imbalanced wireless networks

Abstract

We consider an imbalanced wireless network setup in which a low-power client communicates with a powerful server. We assume that public key cryptographic operations such as Diffie-Hellman key exchange conducted over a large multiplicative group is too computationally intensive for a low-power client to implement. In this paper, we propose an authenticatedk ey exchange protocol such that it is efficient enough to be implemented on most of the target low-power devices such as devices in sensor networks, smart cards and low-power Personal Digital Assistants. In addition, it is secure against dictionary attacks. Our scheme requires less than 2.5 seconds of pure computation on a 16MHz Palm V andab out 1 secondfor data transmission if the throughput of a network is 8 kbps. The computation time can be improvedto 300 msec andthe transmision time can also be reduced to 300 msec if caching is allowed. © Springer-Verlag Berlin Heidelberg 2002.