A 5.1μJ per point-multiplication elliptic curve cryptographic processor

Security features such as privacy and device authentication are required in wireless sensor networks, electronic IDs, RFID tags and many other applications. These features are provided using cryptography. Symmetric key cryptography, where the key is distributed between the communication parties prior to communication, doesn’t provide adequate solution for large scalable systems such as sensor networks. In these cases, public-key cryptography (PKC) should be used. However, public-key algorithms are typically more computationally intensive than their symmetric key counterparts, which creates difficulties in meeting the strict area, power and energy requirements. Elliptic curve cryptography (ECC), due to relatively small operand sizes, can be used to answer the imposed challenges. In this paper we present a processor for ECC over GF(2). This processor can perform elliptic curve (EC) point multiplication as well as general modular operations. The processor is flexible enough to support multiple cryptographic protocols. The chip is fabricated using UMC .13 μm 1P8M process, resulting in a core area of 0.54 mm. The energy consumption to perform one EC point multiplication is 5.1 μJ. The design features lightweight countermeasures against sidechannel attacks. A security evaluation shows the effectiveness of such countermeasures.