Sumitomo Corporation has joined a consortium that will develop and operate a high-capacity submarine cable system connecting Japan with key markets across Southeast Asia, strengthening regional digital infrastructure and international data connectivity.
I AM Cable to position Japan as a regional data hub
According to a joint press release, the new system—named the I AM Cable—will span approximately 8,100 km and deliver a total design capacity of around 320 terabits per second (Tbps). The system will support cloud service providers, telecom carriers, and hyperscale data traffic across Asia, while reinforcing Japan’s role as a regional data hub.
To manage the project, Sumitomo will partner with NTT DATA and JA Mitsui Leasing to establish Intra Asia Marine Networks Co., Ltd. (I AM NW), a Tokyo-based operating company. I AM NW will oversee system planning, development, and the commercial sale of transmission capacity.
Connecting Japan to Southeast Asia and beyond
The submarine cable will link landing stations in Chiba, Mie, and Fukuoka with Malaysia and Singapore. The consortium also plans future connections to South Korea, along with later extensions to the Philippines and Taiwan.
Fukuoka plays a central role in the project’s long-term strategy. Developers are positioning the city as an international telecommunications hub for western Japan, supported by emerging data center clusters designed to attract hyperscale and international traffic.
Advanced SDM technology enables scalable capacity
The I AM Cable will deploy space division multiplexing (SDM) technology, supporting up to 16 fiber pairs—or 32 cores—per cable. The system will also incorporate wavelength selective switch functionality, allowing operators to remotely reallocate spectrum between routes.
This architecture will enable the system to achieve its 320 Tbps design capacity while maintaining flexibility to adapt to changing traffic patterns over its operational lifetime. The consortium expects the system to enter service in early fiscal 2029.
Expanding Sumitomo’s subsea infrastructure footprint
While the announcement did not specify cable supply responsibilities, the consortium stated that Sumitomo will leverage its extensive networks and broad customer base to support the project’s commercial success. The move aligns with Sumitomo’s broader expansion into subsea and digital infrastructure, following investments such as the JUNO Cable System linking Japan and the United States and other global digital assets.
Additional information about Sumitomo Corporation’s infrastructure activities is available at https://www.sumitomocorp.com.