Key Distillation is an essential component of every quantum key distribution (QKD) system because it compensates for the inherent transmission errors of a quantum channel. However, the interoperability and throughput aspects of the post-processing components are often neglected. In this paper, we propose a high-throughput key distillation framework that supports multiple QKD protocols, implemented in a field-programmable gate array (FPGA). The proposed design adapts a MapReduce programming model to efficiently process large chunks of raw data across the limited computing resources of an FPGA. We present a novel hardware-efficient integrated post-processing architecture that offers dynamic error correction, mutual authentication with a physically unclonable function, and an inbuilt high-speed encryption application that utilizes the key for secure communication. Additionally, we have developed a semi-automated high-level synthesis (HLS) framework that is compatible with any discrete variable QKD system, showing promising speedup. Overall, the experimental results demonstrate a noteworthy enhancement in scalability achieved through the utilization of a single FPGA platform.
Key Distillation is an essential component of every quantum key distribution (QKD) system because it compensates for the inherent transmission errors of a quantum channel. However, the interoperability and throughput aspects of the post-processing components are often neglected. In this paper, we propose a high-throughput key distillation framework that supports multiple QKD protocols, implemented in a field-programmable gate array (FPGA). The proposed design adapts a MapReduce programming model to efficiently process large chunks of raw data across the limited computing resources of an FPGA. We present a novel hardware-efficient integrated post-processing architecture that offers dynamic error correction, mutual authentication with a physically unclonable function, and an inbuilt high-speed encryption application that utilizes the key for secure communication. Additionally, we have developed a semi-automated high-level synthesis (HLS) framework that is compatible with any discrete variable QKD system, showing promising speedup. Overall, the experimental results demonstrate a noteworthy enhancement in scalability achieved through the utilization of a single FPGA platform.
Key Distillation is an essential component of every Quantum Key Distribution system because it compensates the inherent transmission errors of quantum channel. However, throughput and interoperability aspects of post-processing engine design often neglected, and exiting solutions are not providing any guarantee. In this paper, we propose multiple protocol support high throughput key distillation framework implemented in a Field Programmable Gate Array (FPGA) using High-Level Synthesis (HLS). The proposed design uses a Hadoop framework with a map-reduce programming model to efficiently process large chunks of raw data across the limited computing resources of an FPGA. We present a novel hardware-efficient integrated post-processing architecture that offer dynamic error correction, a side-channel resistant authentication scheme, and an inbuilt high-speed encryption application, which uses the key for secure communication. We develop a semi automated High level synthesis framework capable of handling different QKD protocols with promising speedup. Overall, the experimental results shows that there is a significant improvement in performance and compatible with any discrete variable QKD systems.
Abstract In the domain of quantum-secure communications, post-processing emerges as a critical mechanism to ensure the security and integrity of the generated keys generated by quantum key distribution (QKD). However, existing post-processing frameworks often lack universality, being highly tailored to single-algorithm implementations and frequently neglecting key aspects such as system scalability and integration. To address these limitations, we present a novel system-on-chip (SoC) architecture for QKD post-processing, built around a co-designed framework featuring a RISC-V soft-core processor. This architecture incorporates core functionalities essential to QKD post-processing, including privacy amplification, information reconciliation, and high-speed communication interfaces. By leveraging the flexibility of the open-source RISC-V instruction set, the system achieves enhanced adaptability and energy efficiency. Additionally, a separated-bus architecture is employed, decoupling data and instruction buses to optimize data transfer efficiency and overall system performance, paving the way for scalable and high-throughput quantum communication systems. The system is deployed on the Xilinx Kintex Ultrascale series development board. At the Bob side, with a frame length of 16 384, the information reconciliation module and the privacy amplification module achieves throughputs of 29.73 Mbps and 131.07 Mbps, respectively.
The proposed research examines the dynamic partial reconfiguration of FPGA (Field-Programmable Gate Array)-based Coherent One Way (COW) protocol and Differential Phase Shift (DPS) protocol key distillation systems. The purpose of the study is to examine the possible advantages of dynamic partial reconfiguration in cryptographic applications, as well as how it affects resource usage and system adaptability. In terms of security and performance, the proposed COW and DPS key distillation systems show positive outcome. They successfully satisfy the needs for secure key exchange and encryption while striking a balance between computational complexity and resource use. Further, the use of dynamic partial reconfiguration improves the overall effectiveness of the cryptographic system by utilizing resources 29.18% lesser than conventional static FPGA designs.
Quantum key distribution (QKD) leverages the principles of quantum mechanics to generate unconditionally secure keys for remote communication, even in the presence of an eavesdropper with unlimited computational power. A critical component of QKD is information reconciliation (IR), which corrects bit errors introduced by system imperfections and channel noise, ensuring the integrity of the shared key. Polar codes-based IR schemes have attracted considerable attention due to their near-Shannon-limit performance and low computational complexity. However, existing implementations primarily rely on CPUs or GPUs, which are suboptimal in terms of performance and energy efficiency. Here, we present a hardware accelerator designed specifically for discrete variable QKD (DV-QKD), targeting polar codes-based IR and implemented on a cost-effective FPGA platform. Our design achieves high throughput and scalability by employing a module-level pipeline parallel structure, a fully parallelized decoding strategy, and a hybrid memory architecture. This approach enhances decoder efficiency and optimizes resource utilization. On this platform, we demonstrate an IR throughput of 35.33 Mbps for a block size of [Formula: see text], providing a real-time, cost-efficient solution that significantly enhances the performance of QKD systems.
Quantum key distribution (QKD), based on quantum mechanics, enables unconditionally secure key exchange even against adversaries with unlimited computing power. As the core of QKD post-processing, information reconciliation (IR) and privacy amplification (PA) ensure key consistency and security by correcting errors and removing leaked information. With the trend toward miniaturized and chip-based QKD systems, post-processing modules require highly integrated designs. FPGAs offer an ideal solution due to their low cost, power efficiency, and flexibility. This paper presents an FPGA-based QKD post-processing architecture using a polar codes-based appending IR algorithm, achieving reconciliation efficiency better than 1.1 under Eµ≥ 0.06 and Rm= 4. A convolution-structured Toeplitz hash module is developed for PA, supporting 53.13 Mbps data rate and 26.45 Mbps key rate with RPA= 0.5. The complete system is implemented on a Xilinx XCKU040 FPGA. Experimental results show support for 176.58 Mbps input, 36.59 Mbps real-time processing, and 17.56 Mbps key output, demonstrating strong performance and engineering suitability. The design features high integration and portability, offering a practical hardware solution for efficient QKD post-processing.
We propose a multidimensional reconciliation encoding algorithm based on a field-programmable gate array (FPGA) with variable data throughput that enables quantum key distribution (QKD) systems to be adapted to different throughput requirements. Using the circulatory structure, data flow in the most complex pipeline operation in the same time interval, which enables the structural multiplexing of the algorithm. We handle the calculation and storage of eight-dimensional matrices cleverly to conserve resources and increase data processing speed. In order to obtain the syndrome more efficiently, we designed a simplified algorithm according to the characteristics of the FPGA and parity-check matrix, which omits the unnecessary operation of matrix multiplication. The simplified algorithm could adapt to different rates. We validated the feasibility and high speed of the algorithm by implementing the multidimensional reconciliation encoding algorithm on a Xilinx Virtex-7 FPGA. Our simulation results show that the maximum throughput could reach 4.88 M symbols/s.