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Risk in Context

The Threat Beneath the Surface: Subsea Cable Vulnerability

Posted by Stephen Harris 14 December 2017

As we become more reliant on the internet to do our banking, shopping, and business communications, we have, perhaps unwittingly, exposed ourselves to a threat from a new form of international warfare – internet disruption caused by sabotage of the global subsea fibre-optic cable network.

You may think that the majority of global communications and cyber links are transmitted via satellites, but, as these cannot cope with the huge volumes of data that the internet increasingly requires, the development of subsea fibre-optic cabling has become the indispensable heart of the communications industry for which there is no viable alternative. Approximately 97% of all such communications rely on these cables, lying on the seabed, deep beneath the oceans.

There has been a lot of focus recently on the need for greater cyber security, whether through increased cyber training, or through greater system protection, but little attention has been paid to the potential threat to this physical, and apparently vulnerable element of the internet.

Deliberate Damage of Cables Presents a Worrying Risk

According to a recent report from UK think tank Policy Exchange, these cables could be vulnerable to being deliberately severed in a terrorist or state-sponsored attack.

The report said “Sabotage of undersea cable infrastructure is an existential threat to the UK. The result would be to damage commerce and disrupt government-to-government communications, potentially leading to economic turmoil and civil disorder.”

Approximately half a million miles of subsea cables lie on the sea floor, unprotected and exposed to the threat of being deliberately severed by any parties that have the capability and resources to carry out acts of sabotage. This could have debilitating effects on the economy, should an extended period of internet downtime occur.

Weapons to cut cables do not need to be sophisticated, and the task is made easier by the fact that the location of nearly all subsea cables is publicly available. As most subsea cables are privately owned and often lie in international waters, national governments have not prioritised their protection. With this in mind, it becomes increasingly apparent that such threats to maritime assets and their potential for consequential disruption to trade, should internet connection be lost, could present business interruption risk for all companies, many of whom may not have previously considered they have any exposure to any marine risks. 

Replacing a severed cable would not only be complex and time-consuming, but the costs would be high. According to Andrew Mackenzie, Claims Advocate at Marsh, “Ensuring that loss prevention measures and effective insurance cover is in place will help mitigate financial strain in the event of an insurance claim,” should the severing of a subsea cable cause interruption for your organisation.

Given the risks and costs associated with subsea cables, Marsh will be looking closer into claims issues in a future report, but in the meantime, Marsh recommends that companies consider this threat to their internet connection, as part of their ongoing due diligence reviews.

Related to:  Claims , Marine

Stephen Harris

Senior Vice President, Technical Advisor, Marine & Cargo