NTT, in collaboration with Nokia and Anritsu, has successfully demonstrated dynamic rerouting of mobile fronthaul using the IOWN All-Photonics Network (APN). The demonstration applied APN technology to the mobile fronthaul between the Radio Unit (RU) and the Distributed Unit (DU) of a 5G RAN base station, proving that dynamic rerouting is possible in under eight minutes without disrupting ongoing user traffic.
With mobile traffic fluctuations based on time and location, operators must maintain unnecessary DU bases to meet demand.
Traditional mobile fronthaul configurations rely on fixed, point-to-point optical fiber connections between RUs and DUs. This static architecture necessitates the continuous operation of all connected DUs, regardless of fluctuating traffic demands, leading to inefficiencies in energy usage. The study explores the potential of the IOWN APN to introduce dynamic rerouting capabilities within the fronthaul network. By enabling flexible reassignment of RUs to different DUs based on real-time traffic patterns, the network can optimize resource utilization. This dynamic approach allows for the consolidation of active DUs during periods of low demand, thereby reducing overall power consumption. Additionally, in scenarios where a link failure occurs between an RU and a DU, the system can swiftly reroute connections to operational DUs, ensuring uninterrupted service and bolstering network reliability.
The IOWN APN enables dynamic rerouting of connections, allowing the system to consolidate resources and reduce power consumption during low-traffic periods. Additionally, in the event of a route failure, alternative DU bases can be activated swiftly to ensure continuous service, enhancing network reliability.

Demonstration Details
The collaborative demonstration involved the deployment of the IOWN APN over a 30 km mobile fronthaul link. The test environment was designed to emulate real-time user traffic conditions. During the demonstration, researchers modified RU configurations and executed optical path adjustments within the APN equipment. The primary objectives were to measure the time required for dynamic route adjustments, assess the impact of these changes on ongoing communications, and evaluate the quality of service post-rerouting.
Key Findings
The results of the demonstration were promising:
• Rapid Rerouting: Dynamic route changes were accomplished in under eight minutes over the 30 km transmission distance.
• Service Continuity: While user traffic on the rerouted path experienced a brief interruption, all other routes maintained normal operation, ensuring minimal disruption to overall service.
• Maintained Quality: Post-rerouting assessments indicated that communication quality metrics, including data transfer speeds and loss rates, remained consistent with pre-rerouting levels.
• Energy Efficiency: The dynamic adjustment of active DUs led to an approximate 20% reduction in power consumption, highlighting the potential for significant energy savings in large-scale deployments.
Contributions of Collaborating Entities
• NTT Corporation: Provided a comprehensive test environment equipped with the necessary 5G mobile communication devices, including RUs and CU/DU units, and spearheaded the execution of the demonstration tests.
• Nokia Corporation: Supplied essential IOWN APN components, such as the Flexible Bridge, APN-T, APN-G, and APN-I devices, and collaborated in conducting the demonstration experiments.
• Anritsu Corporation: Offered precision measurement instruments to evaluate APN latency and verify the proper functioning of synchronization protocols like PTP/Sync-E.
About IOWN and the All-Photonics Network
The Innovative Optical and Wireless Network (IOWN) initiative, championed by the IOWN Global Forum, aspires to revolutionize communication infrastructures by transitioning from traditional electronic-based systems to photonics-based technologies. The All-Photonics Network (APN) is a cornerstone of this vision, aiming to establish end-to-end optical pathways that deliver unparalleled data transmission speeds, ultra-low latency, and enhanced energy efficiency. By leveraging photonic technology throughout the network, from core infrastructures to terminal devices, the APN seeks to create a more responsive and sustainable communication environment.