Bandwidth four times wider than existing 100Gbps line

Daejeon–Chicago link to support research data processing

KT Corp's Gwanghwamun Building West headquarters. [KT Corp]
KT Corp's Gwanghwamun Building West headquarters. [KT Corp]

KT Corp and the Korea Institute of Science and Technology Information (KISTI) have launched the country's first 400Gbps Korea-US dedicated international line for the national science and technology research network, the company announced Wednesday.

The line serves as the international backbone of KISTI's national science and technology research network, connecting KISTI's headquarters in Daejeon to Chicago — a hub for North American and European research networks. The bandwidth on the Korea-US segment is four times the previous 100Gbps capacity.

The upgrade will allow large-scale research data needed for global collaborative projects to be handled more reliably. It is also expected to meet growing demand for cross-border data exchange driven by the expansion of data-intensive fields such as AI, large-scale science and astronomy.

Beyond high-speed transmission of large research datasets, the new line is expected to strengthen the global connectivity of the national research network and expand support for international joint research.

KT Corp and KISTI jointly resolved the technical challenges of securing stable 400Gbps transmission over the long transoceanic Korea-US route. The two organizations completed construction and stability verification of the submarine cable segment and established the interconnection environment through to Chicago.

KT Corp currently operates five submarine cable systems — three in Asia and two in North America — including APG, APCN-2, NCP, TPE and KJCN, accounting for more than half of all submarine cables in operation in South Korea.

The new research network line was added to the NCP submarine cable, which directly connects South Korea and the United States without intermediate routing. This minimizes latency and transit risk on the international segment.

KT Corp operates dual cable landing stations — in Busan and Geoje, South Gyeongsang Province — where submarine cables meet the terrestrial network. If a network problem occurs on a specific segment, international traffic can be continuously rerouted through an alternative path.

KT Corp plans to gradually expand submarine cable capacity and diversify its landing stations to meet rising traffic demand driven by the spread of AI services and increasing global data exchange.

"Building Korea's first 400G Korea-US national science and technology research network is an important milestone that raises the competitiveness of the country's R&D infrastructure to the next level," said Jeon Myeong-jun, executive vice president and head of the Enterprise Service Division at KT Corp's Enterprise Business Unit. "KT will continue to support the strengthening of the national research network's global competitiveness and digital innovation through cooperation with KISTI, drawing on our capabilities in operating international submarine cables and global backbone networks."

Meanwhile, KT Corp announced in July that it plans to invest a total of 6 trillion won ($4.46 billion) in AI infrastructure, including AI data centers and submarine cables. Of that amount, 1 trillion won will go toward submarine cables, with plans to add more than 90Tbps of supply capacity.


woo@heraldcorp.com