Compact and Power Conscious Private-key Cryptosystem for Wireless Devices

This paper presents a compact and low power implementation of AES suitable for wireless networks. Since such networks are usually associated with battery-powered devices, power consumption and computation resources are increasingly important constraints. The proposed design uses combinatorial circuits for the implementation of Rijndael s-box transformations where general composite field properties of the Galois field arithmetic are exploited to reduce the area and power consumptions of the implementation. In this design, the complexity of the s-box transformation is reduced by first mapping elements from GF(2⁸) to elements in GF((2⁴)²). Then various architectures for finding suitable inversion in subfield GF(2⁴) are explored and analyzed in terms of area, speed and power consumptions. NIST recommended confidentiality and the authentication modes of operation are implemented and their performances are also compared.