Emerging ubiquitous devices such as WSN nodes and RFID tags, which have extremely limited resources, require complex cryptographic algorithms for security & privacy. While widely used cryptographic algorithms are known to be strong against computational resources of an attacker, the real threat comes from fault and side-channel attacks which try to extract the cryptographic key by utilizing the flaws in the implementation of an algorithm rather than the algorithm itself, e.g. side-channel attacks exploit information such as timing, power dissipation or electromagnetic emanation. This threat becomes more significant for WSN nodes, or RFID tags, with limited cryptographic capabilities and air as the easily tappable communication medium. Hence, it is crucial that cryptographic algorithms for these devices are implemented targeting side-channel resistance and tamper-resilience as well as performance. This project has three main objectives: 1) Investigation of efficient frequency domain arithmetic algorithms for standard cryptographic schemes; 2) Investigation of the feasibility of area/power-efficient realization of these algorithms for constrained ubiquitous devices through proof-of-concept implementations; 3) Investigation of the potential inherent tamper-resilience and side-chanel resistance of frequency domain arithmetic for robust cryptographic implementations. This timely and interdisciplinary project will draw knowledge from diverse fields such as hardware engineering and applied mathematics to provide security to emerging ubiquitous devices. It will also help with the successful reintegration of Dr. Baktir into the European Research Area and give him the necessary resources to establish his research in Europe. Furthermore, it will significantly help transfer of knowledge to the host through cutting edge research, lasting co-operation with the third country and training of young researchers, and thus contribute to the European excellence in research.