Enhancement of S-AES using chaos for the support of biomedical applications

The simplified AES (S-AES) algorithm is used in Zigbee and sensor networks as a fast encryption method but it is easy breakable and not secure. Thus it doesn´t meet the security requirements of medical applications. On the other hand, ciphers based on chaotic functions seem to be more promising. In this paper, an enhancement of S-AES algorithm is presented. It consists of using a chaotic cipher composed of two maps PWLCMs (Piece Wise Linear Chaotic Map) to improve two functions of S-AES. This enhanced algorithm is particularly adequate for data encryption in ZigBee networks and biomedical sensor networks where robustness and real time are both essential. A comparison between our enhanced algorithm and the original S-AES is presented with regard to robustness.