A design of lightweight true random number generator based on Galois LFSR with dynamic feedback path

Abstract

The Linear Feedback Shift Register (LFSR) is a widely utilized circuit structure in electronic systems, often employed as a Pseudo Random Number Generator (PRNG) for generating pseudo random sequence. However, in light of the significant challenges associated with privacy protection and data encryption, traditional PRNGs have frequently failed to meet the increasing security demands of electronic systems. In contrast, True Random Number Generators (TRNGs), have emerged as essential security primitives within the realm of hardware security, garnering increasing attention. In response to these challenges, this paper proposes a novel lightweight TRNG architecture based on Galois LFSR. This innovation design incorporates inverters and two-to-one multiplexers to modify the feedback path. The proposed structure has been implemented on AMD Xilinx Artix-7 and Kintex-7 FPGA boards. Notably, it demonstrates a resource-efficient design, utilizing only 17 Look-Up Tables (LUTs) and 9 D Flip-Flops (DFFs), while achieving random number with throughput of 300Mbps. Furthermore, the structure successfully passes both randomness test and robustness test, indicating its promising application potential in secure electronic systems.