The threat to world’s communications backbone – the vulnerability of undersea cables

Undersea data cables are critical to the internet upon which the modern world has come to depend. This hidden network forms the backbone of global communications but is surprisingly vulnerable to interference by hostile actors. Protecting this infrastructure may become an increasingly important remit for the Royal Navy.

Background

The first undersea cables were telegraph cables laid by Britain to maintain communication across its empire in the second half of the 19th Century. Telegraph cables were gradually replaced by telephone cables and in the 1980s fibre optic technology revolutionised the volume of data that could be carried by a single cable. As the internet revolution began, this fibre optic cable network expanded and new cables continue to be laid across the globe. At least 97% of all internet and voice data now passes through this network.

A data cable is typically about the same circumference as a garden hose for most of its length, although sections closer to shore have thicker sheathing, are buried in trenches cut below the seabed or even have mating laid over them for protection. Specialist cable laying ships are employed and keep to carefully planned and surveyed routes, avoiding natural obstacles such as reefs, wrecks, sharp drops and inclines and areas of known seismic activity. Besides intentional damage, cables have been accidentally cut by ship’s anchors, fishing activities and have even been attacked by sharks. Laying submarine cables is expensive and time-consuming, demanding the investment of hundreds of millions of dollars before a return is made. To date, more than 1.2 million km of submarine cables have been laid in the oceans of the world, the longest single cable is the Asia-America Gateway (AAG) cable system which runs for over 20,000 km. A typical modern subsea cable is made up of up to 200 fibres, each able to transmit 400Gb of data per second in both directions.

Interference with submarine cables for strategic ends began in earnest during the First World War when Britain cut Germany’s undersea telegraph cables in the English Channel. The single remaining German cable was tapped by Britain allowing it to read messages. In response, the Germans attempted to destroy allied cables and signal stations in the Pacific and Indian Ocean with limited success. Most of this sabotage did not require sophisticated equipment and was usually done in relatively shallow waters by surface vessel using grappling hooks. However German U-boat, U-151 was fitted with a cutting device and in 1918 managed to sever links between New York and Nova Scotia and New York and Panama. The practice of cable cutting continued in all theatres during the Second World War.

The Cold War inspired a new level of submarine cable interference. The most well-known example is operation ‘Ivy Bells’. The US Navy used SSNs adapted with diver lockout chambers to lay cable tapping devices on Soviet cables that linked the Russian naval base at Petropavlovsk to its mainland headquarters in Vladivostok. The devices recorded conversations on magnetic tapes that were recovered and replaced by regular submarine operations. Between 1971-81, when the tap was revealed to the Russians by a US mole, the recordings provided valuable intelligence and insight into Soviet naval planning. This may have been the tip of the iceberg as the USN likely conducted other tapping operations. In the modern era, Edward Snowden (Heroic privacy rights campaigner/Putin’s useful idiot) revealed to the media that the American NSA and British GCHQ are able to harvest vast amounts of internet data from taps placed both legally or covertly on fibre optic cables all over the world.

Unprotected

Most of the explosion in wealth derived from globalisation relies on high-speed communications, quite small disruptions to connectivity can have consequences disproportionate to an apparently minor event. Even very undeveloped nations can be impacted. Off the coast of Somalia in 2017 a single cable was accidentally cut by a ship’s anchor. The outage lasted 3 weeks and cost the country $10 million each day. Some nations are reliant on just one or two cables while some routes have multiple cables. There are at least 19 TransAtlantic cables that connect Europe to the US, offering a measure of redundancy if one or two cables are cut but traffic levels continue to climb.

Deliberate interference with cables does not necessarily require particularly sophisticated technology because they are clearly marked on charts for mariners and inevitably have to traverse shallow waters. There have been instances where cables have been cut by amateur divers and vandals breaking into terminals on land. Just like shipping routes, the constraints of geography have created many ‘chokepoints’ where cables are forced to pass through narrow straits where they are easier to locate and interrupt.

The cable network is owned and managed by a wide variety of international commercial entities (Google, Facebook and Microsoft are now in the cable-laying business). There is some global management of key software elements of the internet such as that exercised by ICANN, an organisation that manages domain name allocation, but there is no international or even much government oversight of the physical infrastructure. Despite being strategic national assets we are reliant on commercial interest to maintain and repair cables.

When cables fail, initially locating the break is the hardest part. Once found, either an ROV is despatched by the cable layer or grapnel hooks are used to retrieve the ends and bring them to the surface where they must be spliced together by hand. The whole process may take anything from a few days to a few weeks and may depend on weather conditions and the depth of the water. In an open conflict, slow or stationary cable laying vessels following predictable routes to attempt repairs would be very easy targets.

Cut off

The internet was originally conceived by the US Defense Advanced Research Projects Agency (DARPA) in the 1960s as a military communications network that could survive nuclear strikes. If part of the network was destroyed, signals would automatically be re-routed via other parts of the system. Although the underlying structure of the internet still works this way, there is very limited spare bandwidth to cope, especially if multiple cables are severed. The sheer volume of data could not always be re-routed and would likely slow down or cripple activity across large parts of the web. Some communication by satellite would be possible but is vastly more expensive and the available bandwidth is relatively small. Using every communications satellite available in the Earth’s orbit could carry just 7% of the communications currently sent via cable from the United States alone.

While ‘local parts’ of the internet might continue to be accessible if international cables were cut, many critical services rely on data centres that are overseas, particularly the big tech companies based in the US that dominate the web. The seamless and distributed nature of the internet is both its strength and vulnerability. A company’s data may be housed in a data centre located just down the road but the application that processes it may be running on a server on another continent.

In many people’s minds, the internet is associated with entertainment and social media and the possibility of the web going dark for a few weeks might seem like just a potential inconvenience. Behind the scenes, the internet does far more than deliver Netflix or allow pictures of cats to be uploaded to Facebook. Financial transactions worth over $10 trillion each day are done online and any disruption would have an immediate effect on the economy, potentially crippling the banking system and halting commerce.

Not only are consumers increasingly shopping online, but most companies are now entirely reliant on the web to store and access vast amounts of data, handle administration, distribution, intellectual property, send and receive payments and much more.  Few organisations have parallel offline processes in place that could quickly be activated to replace online systems and life in most western societies would be turned upside down without the internet. One of the legacies of the pandemic is going to be an even greater reliance upon online connectivity. Many organisations are considering abandoning or downsizing their offices as employees demand to work remotely at least part-time or with only occasional in-person meetings.

Wake up call

In 2017 the think tank, Policy Exchange published a landmark document written by Rishi Sunak outlining the threat to undersea cables in a UK context. We will not repeat the full content of this excellent work but the piece names Russia as the primary actor developing the capabilities and having the potential motivation to interfere with submarine cables.

Sunak has subsequently experienced a meteoric political rise and now wields enormous influence as Chancellor of the Exchequer. If not the instigator himself, he would certainly have been in favour of investing in “Multi-Role Research Vessels” announced by the Prime Minister in November. In his  Christmas address to the fleet, First Sea Lord mentioned the vessels, labelling them slightly differently as “two new ocean surveillance ships”. He said their purpose would be “to help with data gathering but also help us protect critical national infrastructure and undersea cables.”

The Russian threat

Cutting submarine cables is a deniable activity that would suit a power like Russia that my try to achieve its ends operating in the ‘grey zone’ below the threshold for full-scale war. This kind of asymmetric attack is attractive for a ‘weaker power’, the activity is low risk and for a relatively modest investment and could potentially achieve enormous impact. Russia is dependent on the internet but the Western economies would be much more exposed to loss of connectivity. The UK has been particularly successful in developing its digital economy, even amongst other developed nations and would be especially harmed by a loss of internet access.

Russia is investing in sophisticated naval assets that could be employed to cut specific cables in a targeted and covert way. Submersible with arms that can manipulate objects on the sea bed can place taps, cut cables or leave devices that could cut cables upon command in the future. The research ship Yantar is officially classed as Auxiliary General Oceanographic Research (AGOR), with underwater rescue capability. She is tasked by the shadowy GUGI (Main Directorate Deep-Sea Research) which is an arm of the Russian Defence Ministry but separate from the Navy. Yantar has been seen operating close to seabed cables on several occasions by open-source intelligence analysts and is doubtless tracked much more closely by professional naval intelligence. There is no evidence of nefarious activities yet but Yantar has likely been primarily engaged in information gathering, charting the location and vulnerabilities of cables and other undersea energy infrastructure should they wish to interfere with them in the future.

The US maintains a secretive underwater network of sensors (Formerly SOSUS, now known as the Integrated Undersea Surveillance System (IUSS)) used to track submarine activity. IUSS is increasingly mobile and less reliant on fixed infrastructure but it does still exist and adversaries remain interested in the location of the sensor arrays and supporting cables. As part of its attempts to dominate the Arctic, Russia is known to be laying its own network of arrays under the ice called HARMONY. Incredibly, the system is believed to be powered by a series of small submarine-portable nuclear reactors laid on the seabed.

The construction of such a complicated system is only possible because GUGI operates the largest fleet of covert manned submersibles in the world. This fleet includes six nuclear-powered mini-submarines; 2 x Paltus (730 tons) 3, x Kashalot (1,580 tons) and Losharik (2,100 tons). Supporting them are two large ‘mother’ submarines that can covertly convey their deep-diving babies over long ranges. Although the construction of HARMONY may be the initial task, this transporter submarine capability means the Russians can potentially interfere with submarine cables unseen anywhere in the world’s oceans.

Securing the lines

Protecting cables that stretch for thousands of miles across the deep ocean floor is extremely challenging and potentially expensive but there are three main ways in which security could be improved.

Legal and regulatory. There is limited protection for submarine cables in international law and this could be addressed with a new International treaty with punitive sanctions against any nation proven to have interfered with cables. This would at least help raise the threshold of risk for actors contemplating such action. Cable Protection Zones could also be implemented in areas of shallower waters where vital cables at risk. Areas covered by these regulations would not allow, surface ships conducting ‘research activity’, fishing, ships anchoring or diving. Even assuming all nations would be willing to accept a new treaty,  like all regulation of the marine environment, the primary difficulty is to ensure round the clock enforcement.

Capacity and redundancy. Key data traffic routes could be backed up by redundant extra ‘dark’ cables, ideally not marked on charts and buried as much as possible. There is already some redundancy in the system as accidental cable breaks occur frequently but there is limited financial incentive to invest large numbers of new cables, capable of providing the level of resilience required if a concerted attack cut multiple connections. Building this additional resilience would likely require government funding in partnership with cable companies.

Surveillance and deterrence. It is possible that cables could be fitted with sensors that can detect the sonar frequencies used by submersibles intent on interference and alert authorities ashore. It may also be possible to use fibre optic cables themselves as sensors. Small or unusual movements in the cable caused by interference may be detectable by analysing the transmission of light through the cable. There are already research programmes underway to investigate using undersea cables to measure distant seismic activity.

New developments make the deployment of a fleet of UUVs to patrol up and down sections of cable practical and affordable. Persistent Autonomous Underwater Vehicles (PAUV) that use very little power and are can operate independently for several months are maturing and could be a solution. The deployment of patrol UUVs and the inspection and rapid repair of submarine cables could be a task for the new Ocean Surveillance/Research Vessels. This activity cannot be undertaken by the UK alone and would require co-operation with other nations willing to invest significantly in cable security.

The RAF recently stood up a new ‘Space Command’ with its mission to “protect the UK’s interests in space”. Loss of satellite links would severely hamper military command and control systems, communications and ISR in particular, but cutting a few seabed cables has the potential to cause damage measured in hundreds of £Billions and affect every aspect of society. The ability to disrupt satellites is limited to a few powerful nations but the bar to disruption of seabed infrastructure is much lower and more easily achieved. Part of the tasking for the newly established NATO North Atlantic Command (based in Norfolk, Virginia) is to monitor threats against undersea infrastructure – the nearest organisation (or ‘Inner Space Command’) currently in existence to address an arguably greater threat.

Unlike the nuclear or cruise missile threat, specific deterrence against data cable interference cannot be maintained with the option to respond in kind. All that can be done is to make it riskier for adversaries to contemplate by improved regulation and surveillance. In broader terms, further improvements in anti-submarine and underwater warfare capability for the RN and across NATO is needed. Small steps such as the new RVs and the procurement of the Manta XLUUV technology demonstrator are moves in the right direction but there is much more to be done to secure the backbone of global communications.