Samiela Funua, head of cables in Tonga, said staff could not assess the cable situation while there was still volcanic activity. Image credit: ABC screenshot
A roadmap for submarine internet cables in the Pacific as of May 2021. Image credit: ABC screenshot
According to foreign media reports, due to the impact of the submarine volcanic eruption, the submarine cable in the South Pacific island country of Tonga has been confirmed to be cut off, the national telephone and network lines have been interrupted, and about 105,000 residents on the island have been unable to contact the outside world. Dean Vevelka, head of networking at New Zealand's Southern Cross Cable Network, said it "could take two weeks" to fix the cable.
Today, submarine cables are the cornerstone of globalization and global communication. Millions of kilometres of submarine cables surround the globe, providing internet and communications connectivity between continents. For countries around the world, especially coastal or island countries such as Australia, Tonga, fiji, etc., submarine cables are an important infrastructure and vital to the daily operation of society.
The destruction or disruption of this critical infrastructure could have catastrophic consequences locally, regionally and even globally. This is exactly what happened in Tonga after disasters such as volcanoes and tsunamis. But this is not the first time a natural disaster has cut off vital submarine cables, nor will it be the last. Australia's Dialogue magazine said that the volcanic eruption in Tonga actually revealed the fragility of the global telecommunications system.
What happened to the Tonga submarine cable?
Tonga has only been connected to the global submarine telecommunications network for the past decade. The island nation relies heavily on submarine cable communication systems because it is more stable than other technologies such as satellites and fixed infrastructure.
The current situation in Tonga remains volatile, and some details have yet to be confirmed. Currently, the island of Tonga is covered in volcanic ash, with disruptions to submarine network cables and telephone signals, as well as Internet signals, which seriously affects its online services.
According to the Dialogue article, Tonga is particularly vulnerable to such disturbances. Because Tonga's capital, Nuku'alofa, and Fiji are connected by only one cable, this submarine cable is 872 kilometers long, it is the key to Tonga's connection to the rest of the world.
The latest news from the Australian Broadcasting Corporation on the 18th said that Samiela Funua, director of Tonga Cable, said that the cable was cut in two places, but until the volcanic activity stopped, maintenance personnel would not be allowed to contact the cable.
Dr Amanda Watson, a researcher in the Department of Pacific Affairs at the Australian National University, said the cable connecting Tonga and Fiji had been damaged before. In 2019, the cable broke in at least two places, and the repair took about two weeks.
Dr Watson said: "Tonga is not the only Pacific island that relies on a single cable to connect to the outside world, and hopefully more cable arrangements will be seen in place in the future to avoid a complete disruption like this one." ”
Submarine cable risks are not unique to Tonga
There are currently about 428 submarine cables in the world, with a total length of 683508 miles (about 1.1 million kilometers), providing Internet and communications connections to countries and regions around the world.
In the event of a major failure, such networks can become overloaded, especially if they are hit by natural disasters.
Cables are laid at the shortest distance between two points on the earth's surface, which is done because of the lower cost. They must also be laid along specific geographical locations that are easy to place, which is why many cables are concentrated in some "choke points", such as the Hawaiian Islands, the Suez Canal, Guam and the Shunda Strait in Indonesia. But the trouble is that these areas are also often the places where major natural disasters occur.
Once damaged, it can take days to weeks, or even longer, to repair the cable, depending on the depth and accessibility of the cable. In times of crisis, such blackouts make it more difficult for governments, emergency services and charities to participate in the recovery effort.
Many of these submarine cables are close to or directly past active volcanoes, which are areas affected by tropical cyclones and/or active seismic zones.
Not only Tonga, but also submarine cables in countries and regions such as Australia and New Zealand are very fragile. Australia, for example, is only connected to a global communications network from Sydney and Perth via a very small number of connection points. Previously, there have been large underwater landslides on the coast of Sydney. In the future, similar incidents are likely to disrupt the key "arteries" of local networks.
Dr Anthony Birkin, senior researcher at the Strategic Policy Institute in Australia, said more work was needed to ensure cables were more resilient in the future.
How do you manage future risks?
The Conversation article said that the events in Tonga once again highlighted how fragile the global submarine cable network is and how quickly we can "drop the line".
Given the fragility of submarine cable communication networks, the first step in risk reduction is to conduct research to quantify and assess the actual risk of submarine cables to specific places on the seabed and to different types of natural disasters. For example, tropical cyclones (hurricanes/typhoons) occur frequently, but other disasters such as earthquakes and volcanic eruptions occur less frequently.
The second is to achieve global data sharing. Currently, there is little publicly available data on the risks of the global submarine cable network. Once they understand which cables are vulnerable and which types of hazards are vulnerable, countries can develop risk mitigation plans.
At the same time, Governments and telecommunications companies should find ways to ensure diversification of communication modalities, for example through the use of more satellite-based systems and other technologies, thereby reducing reliance on submarine cable communication systems. (Intern reporter Zhang Jiaxin)
Source: Science and Technology Daily