Does a Shark Attack the 'Internet' with Sharp Teeth? [Im Juhyung's Tech Talk]

Undersea Cables Carrying 90% of Global Internet Traffic
Occasionally Damaged by 'Shark' Attacks
Clear Reasons for Cable Attacks Remain Unknown

A great white shark, a species of the family Lamnidae. / Photo by Yonhap News

[Asia Economy Reporter Lim Juhyung] Life without the internet is unimaginable. Especially nowadays, with active discussions on the 4th industrial revolution, including 'drone taxis,' if online connectivity is lost, the entire industry could be shaken. However, that crisis might ironically be caused by sharks. Sharks with sharp teeth can bite the internet cables laid deep on the seabed (the ocean floor). Of course, preparations against this are currently well in place, but due to the possibility, some speculate that sharks might be attacking the internet.

According to data from the UK IT market research firm 'TeleGeography,' over 99% of global internet and mobile traffic is transmitted via submarine cables. Their publicly available 'Submarine Cable Map' shows that as of last year, a total of 1.3 million kilometers of submarine cables are laid across the world's oceans.

The problem lies in the unstable environment where submarine cables are laid underwater. Undersea volcanic activity, earthquakes, and tsunamis can damage the cables, and fishing vessels floating on the surface may damage cables while lowering their nets. According to the International Cable Protection Committee (ICPC), over 70% of cable damage and failure incidents are caused by fishing vessels and natural disasters.

However, occasionally, marine creatures?especially sharks?also cause damage to submarine cables. In other words, sharks are attacking the internet.

The first recorded shark attack on cables was in 1985. The American telecommunications company AT&T was laying the experimental fiber optic cable 'TAT-8' near the Canary Islands off the coast of Africa.

During repairs on a faulty cable, AT&T employees discovered shark tooth marks on part of the cable. Additionally, in the same year, four submarine cables installed in the Atlantic Ocean were damaged due to shark attacks. Since then, scenes of sharks approaching or biting submarine cables have been occasionally captured.

A shark biting an internet cable laid on the Pacific Ocean floor in 2014. / Photo by YouTube capture

Because of this, whenever the internet became unstable, jokes about 'sharks biting the cables' would surface.

Scientists have spent decades researching why sharks bite cables.

In 2014, Google's cable research division proposed the 'magnetic field confusion theory.' The core idea is that sharks might mistake the magnetic field generated by the electricity flowing through submarine cables for prey and bite them.

Sharks are known to be highly sensitive to magnetic fields and ultrasound, thanks to a body part called the 'ampullae of Lorenzini,' which detects subtle electrical currents around them. However, it has not yet been confirmed whether sharks can mistake the strong magnetic fields emitted by high-voltage electricity in cables for prey.

A simpler explanation exists as well. Professor Chris Lowe, who works at the 'Shark Lab' at California State University, explained in 2017 that sharks might bite cables simply out of curiosity.

Professor Lowe said, "If a plastic piece that looks like a cable is in the middle of the ocean, it’s natural for a shark to bite it at least once. The problem is that even if such incidents happen very rarely, if a cable is damaged, thousands of people can be affected."

Underwater cables for export are being loaded at the LS Cable & System Donghae plant. / Photo by LS Cable & System

So, what is the probability of submarine cables being damaged by sharks today? To conclude, the probability is very low.

The ICPC investigated all submarine cable damage incidents from 1957 to 2015 and found that since 2006, cable damage caused by sharks accounts for less than 1% of all incidents. The ICPC pointed out in this report that the shark attack theory often claimed on YouTube and media is somewhat exaggerated.

The sharp decline in shark-related cable damage is due to the development of various methods over the past decades to protect cables from sharks.

Firstly, recent construction methods have greatly advanced, such as digging the seabed with plows or using underwater drones to carve grooves before laying submarine cables. Thanks to this, underwater creatures like sharks find it difficult to approach the cables.

Also, cable designs have been modified to become more robust. For example, Google has added Kevlar coating?a material used in bulletproof vests?to the cable coverings. Because of this, the latest submarine cables are so tough that sharks cannot even scratch them with their teeth.

Rather, the biggest challenge for submarine cable managers recently is fishing vessels. As cable networks have expanded, cables are often laid in shallow waters around 200 meters deep, where ships floating on the surface increasingly cause damage by hitting cables with various equipment.

According to the ICPC, incidents where ship anchors or fishing vessel equipment collide with and damage cables now account for up to 75% of all cable damage cases.

Meanwhile, the global submarine cable market is dominated by companies from four countries?France, Italy, Japan, and Korea?forming the so-called 'Big 4.' Although Korea entered the market late in 2008, it has secured projects worldwide, including Europe and the United States, surpassing several countries. We look forward to Korea leading the submarine cable competition market by overcoming the extreme underwater environment.