An All-Optical Metro Network With Hybrid Optical Circuit Switching and Optical Time-Slot Switching for Heterogeneous Access Services

Next-generation optical metro networks need to support massive radio access nodes, edge computing nodes and residential users with a higher level of dynamicity and flexibility, lower and deterministic latency, and improved energy efficiency. In this context, an all-optical end-to-end network infrastructure enabling massive connectivity and dynamical reconfiguration is necessary. In this paper, we investigate the state-of-the-art all-optical metro network technologies. We analyze their limitations and propose a new network architecture called MOON (<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">M</i>etro <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">O</i>ptical Circuit Switching and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">O</i>ptical Time-slot Switching <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</i>etwork). MOON is an all-optical metro network with the “One Fits All” concept, designed to serve converged fixed, mobile, and edge computing services. In the optical layer, MOON utilizes hybrid optical switching (HOS), which combines optical circuit switching (OCS) and optical time-slot switching (OTS) to offer variable granular optical channels for diverse access traffic. This approach ensures efficient wavelength utilization and immediate response to communication requests. In the transport layer, MOON encapsulates diverse client traffic and implements network slicing using optical service unit (OSU) technologies. In addition, a hierarchical QoS-aware scheduling method is proposed to map different client traffic flows into MOON network while meeting their QoS requirements. Numerical results show that MOON achieves up to 28% and 77% of wavelength savings compared to OCS-based networks under different network scales, and MOON with the proposed network slicing can allocate the appropriate amount of network resources to different types of client traffic according to their QoS requirements.