NTT Communications, KDDI, SoftBank Corp and Rakuten Mobile agreed to jointly build a fibre-optic submarine cable connecting Hokkaido and Akita Prefecture with a planned capacity of more than 160Tb/s.

KDDI stated deployment of the 770km cable is expected to be completed by the end of 2023. Using the latest optical wavelength division multiplexing transmission systems, it will connect the cities of Otaru and Akita.

The operator noted the cable is designed to provide large-capacity and increased redundancy as the area experienced a number of large-scale disasters in recent years.

In a related, separate statement, Rakuten Mobile explained the joint deployment offers more cost-effective construction of 5G infrastructure, noting it backed the cable rollout to keep up with the expected increase in traffic driven by rising adoption of the mobile technology and other high-speed, high-capacity networks.

NTT Communications noted the cable will enable it to create a redundant configuration with three routes between Hokkaido and Honshu, including those it already owns.