Asymmetric Encryption in Wireless Sensor Networks

Abstract

Additional information is available at the end of the chapter http://dx.doi.org/10.5772/48464 IntroductionA Wireless Sensor Network (WSN) is composed of autonomous devices called sensor nodes that generally have low computational power, limited data transmission and power constraints. A WSN consists of sensor nodes that capturing information from an environment, processing data and transmitting them via radio signals. WSNs are increasingly present in our days and can be found in environmental 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 conventional 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 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 algorithms Elliptic / Hyperelliptic Curve Cryptography (ECC / HECC) were created in 80s, and are based on the difficulty of solving the discrete logarithm problem on elliptic curves and hyperelliptic respectively. Despite its complexity the algorithm based on elliptic and hyperelliptic curves have been extensively studied in academia. Recently, the public key algorithm called 1 U.S. Agency for technology that has a partnership with industry to develop and apply technology, measurements and standards. Further information: www.nist.gov

Asymmetric Physical Layer Encryption for Wireless Communications

“…Therefore, we prefer the use of asymmetric PLE (APLE or public key) to reduce the complexity of key distribution and key management. There are already many mature asymmetric encryption algorithms in the upper layers [23], [24], but there is very little work in the physical layer. Of relevance is the work [12] in which a method was proposed using a massive MIMO channel as the key between the sender and the desired receiver, but this method requires the transmitter to know the channel state information for precoding which may be impractical for some scenarios.…”