An Efficient Hardware Implementation of Lightweight Block Cipher Algorithm CLEFIA for IoT Security Applications

IoT 보안 응용을 위한 경량 블록 암호 CLEFIA의 효율적인 하드웨어 구현

Bae, Gi-chur;Shin, Kyung-wook

  • Received : 2015.10.06
  • Accepted : 2015.11.24
  • Published : 2016.02.29


This paper describes an efficient hardware implementation of lightweight block cipher algorithm CLEFIA. The CLEFIA crypto-processor supports for three master key lengths of 128/192/256-bit, and it is based on the modified generalized Feistel network (GFN). To minimize hardware complexity, a unified processing unit with 8 bits data-path is designed for implementing GFN that computes intermediate keys to be used in round key scheduling, as well as carries out round transformation. The GFN block in our design is reconfigured not only for performing 4-branch GFN used for round transformation and intermediate round key generation of 128-bit, but also for performing 8-branch GFN used for intermediate round key generation of 256-bit. The CLEFIA crypto-processor designed in Verilog HDL was verified by using Virtex5 XC5VSX50T FPGA device. The estimated throughput is 81.5 ~ 60 Mbps with 112 MHz clock frequency.


CLEFIA;lightweight block cipher;information security;IoT security;secret key cryptography


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Supported by : Kumoh National Institute of Technology