Low-energy key exchange for automation systems

Abstract

There is a clear trend towards the use of wireless communication in automation systems (AS). To make wireless communication systems usable for automation systems, it is crucial that they fulfil the strong requirements with respect to latency and security. For ensuring security features such as confidentiality and data integrity cipher algorithms are used. In this paper we focus on the most important operation in crypto-systems i.e. the key distribution. As the major part of the devices is resource constraint, energy efficiency is of utmost importance. In this paper we propose to combine the EC ElGamal encryption approach corresponding to [1] with the Montgomery kP algorithm using projective Lopez-Dahab coordinates [4] for realizing the key exchange. The proposed combination helps to reduce the energy needed for exchanging a shared secret key by 30%. This is mainly achieved by reducing the number of bits to be transmitted.