###### Abstract  
Quantum Key Distribution (QKD) offers a revolutionary approach to secure communication, leveraging the principles of quantum mechanics to generate and distribute cryptographic keys that are immune to eavesdropping. As QKD systems become more widely adopted, the need for robust monitoring and management solutions has become increasingly crucial. The Cerberis3 QKD system from ID Quantique addresses this challenge by providing a comprehensive monitoring and visualization platform. The system's advanced features, including central configuration, SNMP integration, and the graphical visualization of key performance metrics, enable network administrators to ensure their QKD infrastructure's reliable and secure operation. Monitoring critical parameters such as Quantum Bit Error Rate (QBER), secret key rate, and link visibility is essential for maintaining the integrity of the quantum channel and optimizing the system's performance. The Cerberis3 system's ability to interface with encryption vendors and support complex network topologies further enhances its versatility and integration capabilities. By addressing the unique challenges of quantum monitoring, the Cerberis3 system empowers organizations to leverage the power of QKD technology, ensuring the security of their data in the face of emerging quantum computing threats. This article explores the Cerberus3 system's features and its role in overcoming the monitoring challenges inherent to QKD deployments. quantum key distribution (QKD); monitoring and visualization; Cerberis3 QKD system; quantum bit error rate (QBER); secret key rate; link visibility +
Footnote †: journal: Quantum Reports  
to secure their data in the face of emerging quantum computing threats. The Cerberis3 Quantum Key Distribution (QKD) system from ID Quantique offers advanced network monitoring capabilities that enable administrators to configure and monitor complex QKD network topologies [4]. The system supports a range of network configurations including point-to-point, relay, ring, and hub-and-spoke topologies. Administrators can configure the Cerberis3 nodes, links, and routes through a central equipment management system (EMS) that provides status updates on each QKD node. The system also provides Syslog and SNMP feeds that can be integrated into the customer's management system. SNMPv3 is recommended for secure monitoring, offering authentication, encryption, and fine-grained access control [5, 6]. Key performance metrics that can be monitored and visualized for the Cerberis3 QKD system include the Quantum Bit Error Rate (QBER), the secret key rate, and the link visibility [7, 8]. The QBER measures the errors in the quantum channel, which must be kept low to ensure secure key distribution [8]. The secret key rate indicates the speed at which secure keys are generated and distributed [8]. The link visibility measures the signal-to-noise ratio in the quantum channel, which impacts the maximum distance and key rate [8]. By leveraging the advanced monitoring capabilities of the Cerberis3 system, network administrators can ensure the reliable and secure operation of their QKD infrastructure, enabling the widespread adoption of this quantum-safe technology. The Cerberis3 Quantum Key Distribution (QKD) system from ID Quantique offers advanced integration capabilities with various network topologies. This system supports deployment in any network configuration, including point-to-point, relay, ring, and hub-and-spoke topologies. Each QKD network node features a Key Management System (KMS) software 2.0.24 hosted on the Quantum Node Controller (QNC) blade, arbitrating key distribution between QKD blades and key consumers such as network encryptors. This ensures the secure distribution of keys across the network based on the recipient's location. The QKD-based quantum-enhanced communication has been explored in detail in [9], also covering how it may be applied in 6G-based networks. The 'quantum Internet' term is introduced, describing a new method for data transmission.