Optimized Optical-Wireless Networks Convergence: Enabling Low-Latency xRANs via Hybrid Split and Reconfigurability

With the imminent arrival of the 5G and future 6G wireless network epochs, which require ultra-low latency services for applications like autonomous vehicles and augmented reality, the advancement of xRANs (cloud/virtualized/open radio access networks) introduces novel challenges to the fronthaul and backhaul networks. To effectively address this, the development of novel programmable converged optical-wireless networks with exceptional flexibility becomes crucial for the future of xRANs.

This study focuses on optimizing converged optical-wireless networks, empowered by open reconfigurable optical add/drop multiplexer (ROADM) technology, to facilitate high-capacity, low-latency, and energy-efficient 5G/6G end-to-end services. By appropriately deploying fast reconfigurable ROADMs through centralized control systems like software-defined networks (SDNs) and dynamic switching of radio equipment, a balance can be struck between conserving network resources and minimizing power consumption plus latency.

In this work, we investigate the feasibility of integrating high-layer and low-layer splits within the same network to achieve this objective. High-layer splits are needed for low latency in time-sensitive tasks, while low-layer splits suit non-time-critical broadband services. This work explores multiple aspects of converged optical-wireless networks, including the integration of mixed splits and the potential of open ROADMs for designing low-latency systems.

The paper concludes with a latency analysis and a cost evaluation of the networks in relation to their latency values. This article aims to assist network planners in making well-informed decisions that balance performance, cost, and latency requirements in upcoming network deployments.