Design of Low Power and High Speed Hummingbird algorithm

Hummingbird is a new ultra-light cryptographic algorithm targeted for resource constrained devices like Radio Frequency Identification ( RFID) tags, smart cards and wireless sensor nodes. In this project we implement an encryption and decryption on the low cost Xilinx FPGA .This project present a technique to reduce power consumption and improves the operating speed and hence the frequency. This reduction allows faster encryption and decryption of the message. The result based on a rough theoretical analysis and logic synthesis showed its efficiency in encrypting and decrypting the message. Index Terms — RFID, Cryptography, Hummingbird, Encryption, Decryption 1. INTRODUTION RFID tags, smart cards, and wireless sensor nodes and various such smart devices, with their wide range of applications, have gained importance in home automation and health care facilities. Many applications involve complicated processing of sensitive personal information and analysis of biological data. however it is necessary to maintain high confidentiality o f o ur d a ta . Thus there is an increasing demand for integrating cryptographic functions into an embedded applications and improvising them. But the important issue that is to be considered is that the smart devices have extremely constrained resources with respect to memory, power supply etc., thus it is impractical to use classical cryptographic algorithms due to security purpose. Moreover, the tight cost constraints also bring forward impending requirements for designing new cryptographic primitives that can perform strong authentication encryption and decryption , and provide other security such as functionality for ultra-low-power applications in the era of pervasive computing. This emerging research area is usually referred to as lightweight cryptography. Hummingbird is the recently proposed lightweight cryptographic algorithm[1]. Hummingbird has a hybrid structure of both block cipher and stream cipher of small block size. This algorithm is intended to be used in resource constrained devices, such as embedded applications and low end microcontrollers. Hummingbird can also be used for authentication as it produces 64 bit authenticator [2] for the message which ensures confidentiality and integrity of the messages. Hence Hummingbird is also known as the Authentication Algorithm. 2. THE HUMMINGBIRD CRYPTOGRAPHIC ALGORITHM Hummingbird is a classic combination of block cipher and stream cipher with 16 bit block size, 256 bits key size and 80 bits of internal states. Both initialization and encryption mechanism of Hummingbird Cryptosystem utilizes 4 block ciphers each of 16 bits, 4 internal state registers and a 16 bit LFSR(Linear Feedback Shift Register).Moreover the 256 bit symmetric key is divided into four 64 bit sub keys k1,k2,k3 and k4[2] which are used in four block ciphers respectively. After the initialization phase of the Hummingbird, the 16 bit plaintext is enciphered by passing four similar block ciphers {i:1,2,3,4}which is a typical substitution-permutation network that alternates between confusion and diffusion[3]. The confusion in the cipher is introduced through the use of S-boxes and diffusion is achieved through the permutations. Hummingbird block cipher is a 4 round process initialized using 64 bit random nonce where each round updates the internal states and LFSR. Each regular round comprises of three steps namely Key Mixing, Substitution step(S-boxes),permutation step. The algorithm uses 4 Serpent like S-boxes of size 4*4.The S-boxes used in Hummingbird is completely balanced and nonlinear which ensures that the block cipher is resistant to several attacks. The permutation in the 16 bit block cipher[4] is represented by following transform: L(m)=m XOR (m«6) XOR (m«10); Hummingbird provides tradeoff between cost, size, speed and performance and hence it is targeted for hardware and micro-controller environment. 3. DESIGN AND IMPLEMENTATION In this section an encryption and an encryption/decryption have been implemented on the low-cost Xilinx Virtual model of hardware is designed and verified using Model Sim SE 6.2b and the design is synthesized using the synthesis tool i.e. Xilinx ISE 9.2i Suite. The statements are synthesized using Verilog hardware description language. Vol 05, Article 05360 June 2014 International Journal of VLSI and Embedded Systems-IJVES http://ijves.com ISSN: 2249 – 6556