SoftBank Deploys Optical Network in Japan for Greener Communication Infrastructure

SoftBank announced the successful completion of the nationwide deployment of an all-optical network in core areas of Japan – in partnership with Fujitsu.
SoftBank 5GThe network employs a disaggregated architecture optical transmission system, featuring Fujitsu’s cutting-edge “1FINITY Ultra Optical System T900” (1FINITY T900), aimed at supporting open networks.

This initiative signifies a significant leap towards building communication infrastructure with a lower environmental impact, contributing to the realization of more sustainable and energy-efficient networks.

The optical network leverages optical technology throughout the communications network. Fujitsu’s next-generation optical transmission system facilitates a remarkable reduction in power consumption, up to 90 percent compared to previous networks, by connecting to equipment compatible with all-optical technology and incorporating liquid cooling technology.

Furthermore, when connected to conventional equipment, the latest photoelectric conversion technology reduces power consumption by approximately 50 percent, resulting in a highly energy-efficient and sustainable network adaptable to various connection environments.

By utilizing a pair of optical fibers, SoftBank has significantly enhanced communication performance, achieving high capacity and high-speed transmission of up to 48.8Tbps, approximately double that of conventional networks.

One of the key features of the optical transmission system introduced by SoftBank is the convergence of all optical and IP networks. SoftBank’s IP router, equipped with a long-distance coherent optical transceiver, enables all-optical connections without photoelectric conversion, reducing power consumption by up to 90 percent. The incorporation of IP network technologies, including SoftBank’s SRv6, enhances the flexibility of the network.

Another notable feature is the introduction of closed-loop liquid cooling technology in Fujitsu’s 1FINITY T900, making it the first system globally to utilize this technology in an optical transmission system. This innovative cooling system significantly improves environmental performance, even when connecting to existing devices that are challenging to link to all-optical network devices. The closed-loop liquid cooling technology eliminates the need for facility modifications, providing a highly reliable, maintenance-free system with an expected lifetime of 20 years.

Additionally, the disaggregation C+L ROADM architecture enables system upgrades as needed, with the ability to handle both wavelength bands simultaneously. This flexibility allows for later additions of the L-band after opening only the C-band, providing a network with low power consumption and investment efficiency without requiring extra equipment.

SoftBank aims to build a network that achieves carbon neutrality while meeting the growing demand for data communication, anticipating future networks based on Beyond 5G/6G technology.