Tight integration between classical and quantum networking requires strict synchronization of events between the classical and quantum portions of the network. Time-Sensitive Networking (TSN) as defined by IEEE 802.1Q is limited to accuracy on the order of microseconds due to limitations in time synchronization performance; TSN gate control is thus similarly limited. This work presents a new High-Precision TSN that enables greater accuracy and resolution toward sub-nanosecond TSN gate control and can directly support entanglement distribution, a key component in a software-designed quantum network architecture where classical control can reach deep into the quantum network and directly control time critical operations.
Tight integration between classical and quantum networking requires strict synchronization of events between the classical and quantum portions of the network. Time-Sensitive Networking (TSN) as defined by IEEE 802.1Q is limited to accuracy on the order of microseconds due to limitations in time synchronization performance; TSN gate control is thus similarly limited. This work presents a new High-Precision TSN that enables greater accuracy and resolution toward sub-nanosecond TSN gate control and can directly support entanglement distribution, a key component in a software-designed quantum network architecture where classical control can reach deep into the quantum network and directly control time critical operations.
Quantum networks hold the potential to revolutionize secure communication and distributed quantum computing. However, realizing this potential requires a control plane capable of meeting the demands of quantum systems, including precise timing, protocol heterogeneity, and programmability. Classical network control architectures fall short due to the no-cloning theorem, the fragility of quantum states, and the tight synchronization constraints inherent in protocols such as entanglement swapping. In this work, we propose a novel quantum control plane design that integrates a structured quantum Yet-Another-Next-Generation (YANG) data model and leverages Time-Sensitive Networking (TSN) components to support both centralized control and agent-based control patterns. We evaluate both patterns under network jitter and clock drift using numerical simulations, identifying key trade-offs in timing precision and robustness. We further demonstrate the applicability of our design through the case study of entanglement swapping, a representative protocol that is sensitive to synchronization. Our findings highlight how control patterns can shape the design of time-aware and scalable quantum network architectures.
Quantum information has emerged as a frontier in scientific research and is transitioning to real-world technologies and applications. In this work, we explore the integration of quantum secure direct communication (QSDC) with time-sensitive networking (TSN) for the first time, proposing a novel framework to address the security and latency challenges of Ethernet-based networks. Because our QSDC-TSN protocol inherits all the advantages from QSDC, it will enhance the security of the classical communications both in the traditional TSN- and QKD-based TSN by the quantum principle and reduce the communication latency by transmitting information directly via quantum channels without using keys. By analyzing the integration of QSDC and TSN in terms of time synchronization, flow control, security mechanisms, and network management, we show how QSDC enhances the real-time performance and security of TSN. These advantages enable our QSDC-TSN to keep the balance between and meet the requirements of both high security and real-time performance in industrial control, in a digital twin of green power and green hydrogen systems in distributed energy networks, etc., showing its potential applications in future quantum-classical-hybrid systems.
Telecom standards efficiently enable time synchronization mechanisms in multi-node Quantum Networks (QNs) by combining Synchronous Ethernet (SyncE) and Precision Time Protocol (PTP). The architecture explored in this work utilizes SyncE to provide all connected nodes with a stable and precise frequency reference, adjustable in the range from 1 Hz to 125MHz, obtaining sub-nanosecond temporal jitter in the real-time/quantum plane. This reference is complemented with PTP to provide a distributed time reference for synchronization with a microsecond-level temporal allocation capability. In particular, in the control plane, PTP enables time division multiple access (TDMA) for sharing the quantum channel in multi-node quantum networks QNs. It is demonstrated that the proposed architecture achieves nanosecond synchronous transfer in the real-time/quantum plane and allocates microsecond time windows through the control plane. The theoretical model and experimental results validate performing common quantum communications operations with 98% fidelity and 10−2quantum bit error rate (QBER) at an emission rate of 12.5 Mqb/s. The results confirm that SyncE/PTP synchronization is a viable and scalable solution for future multi-node QN infrastructures.
Time synchronization is crucial in the architecture of modern communication networks, supporting numerous high-stakes applications like financial transactions, autonomous vehicle control, and data center operations. While traditional time synchronization protocols, specifically the Network Time Protocol (NTP) and Precision Time Protocol (PTP), are reliable for various applications, they fall short in scenarios requiring ultra-high precision and resilience. To address these limitations, this paper provides a comprehensive comparative analysis of two emerging quantum technologies, namely Time-Correlated Entangled Photons (TCEP) and Optical Lattice Clocks (OLC). Using Monte Carlo simulations, we examined the synchronization in terms of the accuracy of these technologies under various noise conditions, revealing that while TCEP works perfectly in low-noise environments, its efficacy diminishes significantly with increasing noise levels. On the contrary, OLCs demonstrate consistent performance across various noise levels, making them more versatile for diverse application scenarios. This study is foundational for integrating quantum technologies in time synchronization for communication networks and sheds light on their merits and challenges. Our findings open new avenues for research in scalability, environmental resilience, and the development of hybrid quantum-classical timekeeping systems. Integrating quantum-enhanced time synchronization into a communication network will be the key step for achieving full-fledged Quantum Internet and quantum-enhanced communication networks.
Next-generation industrial automation in Industry 5.0 demands sub-nanosecond time synchronization to enable advanced human-machine collaboration and real-time control systems. Quantum Time Synchronization (QTS), enabled by entangled photon-based quantum networks, offers ultra-precise clock alignment across distributed nodes. However, practical deployment requires an authenticated classical communication channel to exchange timestamped data and extract synchronization offsets. This paper investigates the core tradeoffs between classical channel latency and achievable QTS precision in hybrid quantum-classical networks. Using a discrete-event simulator, we evaluate the impact of various classical network protocols, each with distinct latency characteristics, on QTS performance. Our results demonstrate that even modest latency increases result in degraded synchronization accuracy and increased synchronization jitter, particularly in time-critical industrial contexts. To address these challenges, we propose a combined approach that integrates low-overhead authentication, low-latency communication protocols, and predictive clock drift compensation. Our findings provide actionable guidance for balancing latency, security, and synchronization accuracy in QTS services for future networks.