The Tonga Cable System is an 827-kilometer submarine fiber-optic cable connecting Tonga to Fiji, providing international internet connectivity for the entire nation.

Overview

The Tonga Cable System links Sopu, Nukuʻalofa in Tonga to Suva, Fiji, where it connects to other international networks, including the Southern Cross Cable Network . Commissioned in August 2013, the cable was designed with two fiber pairs and an initial operational capacity in the low tens of gigabits per second, suitable for Tonga's national traffic profile at the time . Over the years, optical upgrades have increased its practical capacity without altering the physical cable .

Ownership and Funding

The cable is owned and operated by Tonga Cable Limited (TCL), a joint venture between the Government of Tonga, Tonga Communications Corporation, and Digicel Tonga . The project was financed with support from the Asian Development Bank (ADB) and the World Bank, with a total investment of approximately $32.8 million, covering civil works, cable procurement, consulting, and taxes . The construction contract was executed by SubCom (formerly TE SubCom).

Extensions and Domestic Connectivity

In April 2018, the cable was extended with a 410-kilometer domestic inter-island segment, connecting the main island of Tongatapu to the outer island groups of Haʻapai and Vavaʻu. This extension, sometimes called the Tonga Domestic Cable Extension (TDCE), improved broadband access across the archipelago .

Disruptions and Repairs

The Tonga Cable has experienced several major disruptions:

• January 2019: The cable broke, temporarily cutting internet access; satellite communications were used as a backup .
• January 2022: The Hunga Tonga–Hunga Ha'apai volcanic eruption caused underwater density currents that severed the cable, disconnecting Tonga from the international internet for 38 days .
• Repairs are complex, requiring specialist ships from SubCom, often deployed from Port Moresby, Papua New Guinea, and can take weeks depending on conditions .

Impact and Significance

The Tonga Cable System provides substantially higher initial capacity (10 Gbps) compared to satellite alternatives and reduces international connectivity costs by at least 50% . It has been critical in stimulating broadband adoption, lowering telecommunications costs, and supporting economic development in Tonga . The cable is considered national infrastructure, emphasizing reliability and accessibility over commercial profit, reflecting its role as a developmental asset .

Technical Summary

• Length: 827 km (Tonga–Fiji)
• Landing Points: Sopu (Nukuʻalofa, Tonga), Suva (Fiji)
• Fiber Pairs: 2
• Initial Capacity: Low tens of Gbps, upgraded over time
• Domestic Extension: 410 km to Haʻapai and Vavaʻu
• Operators: Tonga Cable Limited, Digicel Tonga, Tonga Communications Corporation
• Funding: ADB, World Bank, Government of Tonga The Tonga Cable System remains the sole international fiber link for Tonga, making it a critical piece of infrastructure for the country's connectivity and digital development .