KT has built a 400Gbps-class national science and technology research network connecting South Korea and the United States. Transmission capacity is 4 times larger than before, which is expected to make international joint research using large-scale data in areas such as AI and space and astronomy easier.

KT said on Tuesday it opened South Korea’s first 400Gbps-class single dedicated international line between South Korea and the United States with the Korea Institute of Science and Technology Information (KISTI).

The line serves as the international backbone of the national science and technology research network operated by KISTI and connects KISTI’s headquarters in Daejeon with Chicago in the United States. Chicago is home to major research networks in North America and Europe. With the line in place, transmission capacity on the Korea-U.S. segment of the national science and technology research network increased fourfold to 400Gbps from 100Gbps.

The upgrade is expected to reduce transmission delays or capacity shortages when domestic research institutions exchange large-scale research data with overseas institutions. KT and KISTI plan to use the network to increase large-capacity data transmission speeds and support international joint research and data use in AI and big-science fields.

The two institutions also completed technical verification to stably transmit 400Gbps-class data across the long-distance segment linking South Korea and the United States. KT built the network line on the NCP subsea cable, which directly connects South Korea and the United States without intermediate stops, minimising delays and transit risks that could occur during data transmission.

KT currently operates 5 subsea cable systems: APG, APCN-2, NCP, TPE and KJCN. It also operates landing stations, which connect subsea cables to terrestrial networks, separately in Busan and Geoje in South Gyeongsang Province so that international data traffic can be handled via another route if problems occur on one segment.

KT plans to expand subsea cable capacity and diversify its landing stations to respond to the spread of AI services and growing global data exchanges.

Myung-jun Jeon (전명준), executive director and head of KT’s Enterprise Service Division, said, "Based on our capabilities in operating international subsea cables and global backbones, we will support strengthening the global competitiveness of the national research network."