Since it was invented in 1986, Elliptic Curve Cryptography (ECC) has been studied widely in industry and academy from different perspectives. Some of these aspects include mathematical foundations, protocol design, curve generation, security proofs, point representation, algorithms for inherent arithmetic in the underlying algebraic structures, implementation strategies in both software and hardware, attack models, among others. The main advantage of ECC is that shorter keys (less memory requirements and faster field arithmetic operations) can be used if compared to other cryptosystems, which has made it the ideal choice for implementing public key cryptography in resource constrained devices, as the ones found in the envisioned applications of the Internet of Things (IoT), e.g. wireless sensors. In this application domain, lightweight cryptography has emerged as the one required because of the scarce computing resources and the limited energy in devices. In this paper we present a survey of ECC in the context of lightweight cryptography. The aim of this work is to identify the criteria that make an ECC-based system lightweight and a viable solution for using in practical constrained applications. Representative works are systematically revised to determine the key aspects considered in ECC designs for lightweight realizations. As a result, this paper defines, for the first time, the concept and requirements for Elliptic Curve Lightweight Cryptography (ECLC).

In recent years, the study of lightweight symmetric ciphers has gained interest due to the increasing demand for security services in constrained computing environments, such as in the Internet of Things. However, when there are several algorithms to choose from and different implementation criteria and conditions, it becomes hard to select the most adequate security primitive for a specific application. This paper discusses the hardware implementations of Present, a standardized lightweight cipher called to overcome part of the security issues in extremely constrained environments. The most representative realizations of this cipher are reviewed and two novel designs are presented. Using the same implementation conditions, the two new proposals and three state-of-the-art designs are evaluated and compared, using area, performance, energy, and efficiency as metrics. From this wide experimental evaluation, to the best of our knowledge, new records are obtained in terms of implementation size and energy consumption. In particular, our designs result to be adequate in regards to energy-per-bit and throughput-per-slice.

This paper presents a novel FPGA-based design for the lightweight block cipher PRESENT and its implementation results. The proposed design allows to study area-performance trade-offs and thus constructing smaller or faster implementations. When optimized by area, the proposed design exhibits smaller latency and fewer FPGA resources than representative related works in the literature.

In this work we present a study that evaluates and compares two block ciphers, AES and PRESENT, in the context of lightweight cryptography for smartphones security applications. To the best of our knowledge, this is the first comparison between these ciphers using a smartphone as computing platform. AES is the standard for symmetric encryption and PRESENT is one of the first ultra-lightweight ciphers proposed in the literature and included in the ISO/IEC 29192-2. In our study, we consider execution time, voltage consumption and memory usage as metrics for comparison purposes. The two block ciphers were evaluated through several experiments in a low-cost smartphone using Android built in tools. From the results we conclude that, for general purpose encryption AES performs statistically better although block-to-block PRESENT delivers better results.