Cisco: QRNG Architecture Since quantum mechanics guarantees the inherent randomness of quantum phenomena, there are many possible quantum processes that can be leveraged as a source of randomness, and here, we choose the quantum vacuum noise as the randomness source [4, 5]. In classical physics, vacuum is defined as a state with no particles and energy. While in quantum physics, as shown in FIG. 1, the quantum vacuum state still has no particle but yields an energy fluctuation, which is called quantum vacuum noise. When representing quantum vacuum noise in phase space, we observe that both random variables of position and momentum, follow a Gaussian distribution. Therefore, when these two variables are measured, Gaussian distributed raw random numbers are obtained. In our QRNG system shown in FIG. 1, the quantum vacuum state can be prepared using a dark fiber or a blocked input at the interferometer, and the Gaussian distributed random variable is measured using homodyne detector. The analog signals from the homodyne detector are then sent to low-noise amplifiers (LNAs) for amplification before being sent to the AMD RFSoC for processing. The RFSoC made by AMD is a System-on-a-Chip platform which contains hard- core processors, FPGA fabric, and integrated ADCs and DACs, among other components. The ADCs in the RFSoC are responsible for converting the continuous, analog signals to discrete, digital values, which are raw bits containing both quantum vacuum noise and classical noise. Classical noise creates correlations in the experimental data that reduces its true randomness. To remove these correlations, we perform post-processing on the experimental data in a process referred to as randomness extraction [6]. The final data from the randomness extractor passes commonly used randomness testing software, such as NIST SP 800-22 and Dieharder. The randomness-extracted data is stored in memory in the RFSoC. From there, the random numbers can be transferred to an external computer via Ethernet for local use or uploaded to the cloud as a service. ©Outshift by Cisco 2024 Quantum Random Number Generator 3