Performance Evaluation of Asymmetric Encryption Algorithms in embedded platforms used in WSN Gustavo S. Quirino 1 , Edward David Moreno 2 , and Leila B. C. Matos 3 1 Department of Computer, IFBA, Barreiras, Bahia, Brasil 2 Department of Computer, UFS, São Cristóvão, Sergipe, Brasil 3 Department of Computer, IFS, Aracaju, Sergipe, Brasil Abstract— This paper presents the performance evaluation of asymmetric cryptographic algorithms oriented to embed- ded platforms used in Wireless Sensor Networks (WSN). The RSA algorithms, ECC and MQQ were evaluated on three different platforms: ARM, MSP430 and AVR Atmega128 platforms. We have used the processing time as evaluation criteria. We used the SimpleScalar tool, MSPsim and Avrora for our simulations analysis. The MQQ algorithm achieved the best results in most of the evaluated criteria. In the ARM platform, the MQQ algorithm obtained a processing time 230 times lower than the time of the RSA algorithm. The ECC algorithm has also shown effectiveness in the platforms evaluated, since in MSP430 platform was 4 times faster than RSA algorithm. Finally, we show that MQQ is a promising algorithm for embedded systems used in WSN, but the ECC algorithm is the most recommended by standardized and have already gone through safety testing. Keywords: Wireless Sensor Network, Public-key Cryptography, Performance Analysis. 1. Introduction A Wireless Sensor Network (WSN) is composed of au- tonomous devices called sensor nodes that generally have low computational power, limited data transmission and power constraints. A WSN consists of sensor nodes that capture information from an environment, processing data and transmitting them through radio signals. WSNs are increasingly present in our days and can be found in envi- ronmental area (climatic measurements, presence of smoke), in health area (measurement of vital signs, temperature), home automation (motion sensor and image sensor) and other areas. Generally, WSNs have no fixed structure, and in many cases there is no monitoring station of sensor nodes during the operational life of the network, so a WSN must have mechanisms for self-configuration and adaptation in case of failure, inclusion or exclusion of a sensor node. Security requirements of WSNs are similar to conven- tional computer networks, therefore parameters such as confidentiality, integrity, availability and authenticity must be taken into account in creation of a network environment. Due to limitations of WSNs, not all security solutions designed for conventional computer networks can be implemented directly in WSN. For a long time, it was believed that the public key cryptography was not suitable for WSNs because it was required high processing power, but through studies of encryption algorithms based on curves was verified the feasibility of that technique in WSN. The cryptographic algorithm RSA [1] is currently the most used among the asymmetric algorithms, working from the difficulty of factoring large prime numbers. Standardized by NIST 1 , this algorithm is widely used in transactions on the Internet. The Elliptic Curve Cryptography (ECC)[2], [3] was created in 80s, and are based on the difficulty of solving the discrete logarithm problem on elliptic curves. Despite its complexity the algorithm based on elliptic have been extensively studied in academia. Recently, the public key al- gorithm called Multivariate Quadratic Almost Group (MQQ) [4] was proposed in academia. Experiments performed in the FPGA and PC platforms showed that MQQ is faster than algorithms such as RSA and ECC [4], [5]. Algorithms involved in this study are asymmetric, but each one works with a specific encryption mode. Many studies have evaluated performance of crypto- graphic algorithms in WSNs, but there is no standardization in the performance analysis. As stated by Margi [6] studies on performance evaluation of cryptographic algorithms for WSNs are often quite different in terms of methodology, platform, metrics and focus of analysis, making difficult a direct comparison among the obtained results. Thus, this pa- per describes a theoretical study of cryptographic algorithms such as RSA, ECC and MQQ as well as the performance analysis of these algorithms in embedded platforms used in wireless sensor networks. This paper is organized as follows. Section 2 gives some background about asymmetric algorithms RSA, ECC and MQQ. Section 3 discusses on the simulation environment, describing details of platforms, simulators, compilers and cryptographic libraries that were used in implementation and simulation of algorithms. The section 4 shows the results of the performance evaluation. The section 5 brings the comparison of results between different platforms evaluated and compared with other works. Finally, some concluding 1 U.S. Agency for technology that has a partnership with industry to develop and apply technology, measurements and standards. Further in- formation: www.nist.gov