LFSR based RNG on low cost FPGA for QKD applications

TL;DR

This paper presents a low-cost FPGA implementation of an LFSR-based pseudo-random number generator tailored for Quantum Key Distribution, demonstrating its effectiveness and exploring minimal non-linearity effects.

Contribution

Developed a low-cost FPGA-based LFSR RNG for QKD, with experimental validation and analysis of minimal non-linearity impacts.

Findings

Successfully implemented XOR of two LFSR sequences on FPGA

Generated random sequences suitable for QKD protocols

Explored effects of minimal non-linearity on randomness

Abstract

Linear-feedback shift register (LFSR) based pseudo-random number generator (PRNG) has applications in a plethora of fields. The issue of being linear is generally circumvented by introducing non-linearities as per the required applications, with some being adhoc but fulfilling the purpose while others with a theoretical proof. The goal of this study is to develop a sufficiently ``random" resource for Quantum Key Distribution (QKD) applications with a low computational cost. However, as a byproduct, we have also studied the effect of introducing minimum non-linearity with experimental verification. Starting from the numerical implementation to generate a random sequence, we have implemented a XOR of two LFSR sequences on a low-cost FPGA evaluation board with one of the direct use cases in QKD protocols. Such rigorously tested random numbers could also be used like artificial neural networks or testing of circuits for integrated chips and directly for encryption for wireless technologies.