While many of us are busy worrying about an internet apocalypse at the hands of IoT bots, there are many other ways the global network could be brought to its knees. A little over 350 of them, in fact, are lying at the bottom of the ocean.
Submarine cables stretch across the world, managing almost all the internet’s traffic between them. That’s everything from financial settlement systems through to voice and video calls.
Content distribution networks help to take the load off both systems by situating oft-repeated content closer to its audience, but it must still get to those staging points in the first place.
Typically, when a submarine cable goes down the causes are mundane. A ship dragging its anchor along the seabed was reportedly responsible for cutting direct connections between the UK mainland and the Channel Islands in late November, for example. As a result, telecoms firm JT had to route all traffic to and from the Channel Islands via an alternative link with France.
When human ineptitude isn’t to blame for submarine cable outages, it’s most often nature – earthquakes, cyclones and the like – that take over. But what about intentional human intervention?
We have seen signs of attacks in the past, such as the incident in Egypt in 2013, when three divers were caught attempting to cut undersea cables (although they later said it was a mistake).
Analysts tell us that simple redundancy will protect us, and as the Channel Islands incident showed, there are typically multiple points of redundancy in undersea fibre-optic networks.
These levels of redundancy vary around the world, though, with historically proven single points of failure at several locations along the top of Africa and in south-east Asia.
Even in countries with more developed connections, targeting multiple ingress and egress points could create significant service disruptions.
We have seen what appear to be malicious attacks on cables before. In 2008, the cables connecting Sicily to Egypt were cut, reportedly choking off traffic between Europe and Asia.
Submarine cables are unprotected in deep waters, simply lying on the seafloor. Closer to the coastline, they are often protected by a galvanized coating and shallowly buried.
Then they come ashore, often connecting to terrestrial fibre underneath access covers next to the beach or in small, anonymous-looking concrete buildings.
All these points are potentially vulnerable to different kinds of physical attack.
Experts point out that submarine cables can always be repaired. The question is, how long would this take? It took around two weeks to get the three severed Channel Islands cables back up and running – though this was partly because the ship originally assigned to the job was called away to another.
There are only so many vessels able to perform this highly specialized job, and they’ve been known to face attacks of their own. What would happen if the global fleet were taxed too heavily?
While it may sound like the plot of a Bond movie, the reality is, such attacks are enough of a threat that the Pentagon is taking notice. Recent reports suggest that the US is getting particularly worried about Russian submarine and spy ship activities around undersea cable routes.
Companies such as Microsoft and Google are building out their own submarine fibre, probably more for cost reasons than for resiliency.
On land, and over short stretches of water such as the English Channel, microwave is also proving a lower-latency option than fibre for companies particularly worried about that kind of thing.
Neither hyperscale-owned fibre or bank-commissioned microwave may be predicated on resiliency but it’s certainly a side benefit. For those companies not rich enough to build out their own private internet backbone, however, a little planning might be necessary to ensure that traffic is channelled along several redundant routes.
While corporate providers mull these options, consumers will just have to cross their fingers and hope for the best when they settle down to a video call with Grandma half a world away.
Tom
I’ve often thought about some of the remote place cables come ashore. If they were marked with signs, they would attract attention. If they are unmarked, the chance for accidental damaged seems higher. Are they marked on navigation charts? either way, in my opinion we are a little too dependent on a network that was not really designed to be used for the purposes we use it for. (I’m pretty certain DARPA did not have FB in mind when they created it.)
Bryan
Am I the only one to recall that old episode of Gilligan’s Island? A storm dredged ashore a submarine phone line, setting expectations for a rescue.
anon
Isn’t cable tapping an even greater concern than cable cutting? Russian spying could prove to be more damaging…
Mahhn
Troubleshooting equipment for fiber is very good. The use of lasers measuring timing can tell techs where breaks and switching equipment is. I expect it would be near if not impossible to tap a fiber line without being detected as an extra hop, or damaged line.
In the US tapping equipment was being installed at COs and major switching stations for the NSA prior to 911. In the tech community it was suspected of being done for insider trading, as that became public, it was announced as being done for national security. Rudy Giuliani was called out for investing in the companies supplying the equipment, not from smarts, but from insider information of which companies had been tapped to build the tapping equipment for the government. The senate and congress are exempt from insider trading laws, but he wasn’t, but – he got away with it. Sorry for the tangent, but it is relevant – if you know people, you can get away with anything. Including tapping a nations internet lines.
Julian Rawle
Tapping into a cable on the sea floor is pretty difficult to do because of the water pressure and the likelihood of water ingress into the fibre. Lifting the cable out of the water to tap into it would require a large vessel with an A-frame, assuming you could locate the cable in the first place, and that might attract attention from the coast guard. The best place to tap into a submarine cable is at the cable landing station with the connivance of the cable owner. Most governments give themselves the right to do this if they choose. In any case, you are out of date: Trump says it’s not the Russians!
TonyG
Well we know where the cables come ashore – they are on the charts as “no anchor” areas. Many of the transatlantic cables used to come ashore at Burnham on Sea – not the nearest point but because bringing the cables up the Bristol Channel meant they were protected by sand and mud. The old Radio Station went a decade or two ago (now a housing estate) and so these are probably unused. But it highlights the point – by tradition they are marked on charts as “no anchor” areas so that everyone knows where they are. Don’t show them and they’ll be damaged accidentally.
Julian Rawle
A reasonably well-informed article but a bit too much suggestion of vulnerability to malicious attack or hacking. “Targeting multiple ingress and egress points could create significant service disruptions” if it were feasible. Attacking the cables under the water is a non-starter. You would have to go for the cable landing stations if you can find them. A synchronized attack on multiple landing stations that are physically miles apart would require significant effort. MIss one and all the traffic could be switched to that route. I do not want to highlight them here but I suggest that there are far more significant vulnerabilities in the network on land than at sea. So the cables in the water can be marked on a chart for safety because no one in their right mind is going to try to damage a cable in 1000m of water and its ok not to highlight cable landing stations because they are usually some distance from the shore with no chance that a ship is going to run into one! If the global fleet was “taxed too heavily” and repair times started to increase costs for operators, the laws of supply and demand would apply and provide incentive for new vessels to enter the maintenance market. I doubt that the Pentagon is really concerned about a Russian sub tapping into a transatlantic cable for the reasons above but the FCC has mandated new reporting of submarine cable outages so that a response to cable damage from some massive disaster e.g. hurricane could be co-ordinated better. Microwave as an alternative to fiber? I don’t think so. Microwave only operates over relatively short distances. I suppose you could string up a line of dishes in an offshore wind farm array but still, you would need a massive amount of power to match the capacity of fibre and you would always be subject to rain fade. There is more work to be done to increase the resiliency of the global submarine network by building more cables as the economics justify so doing, but these days, to suggest that your Internet-based call to Granny is only “best-efforts” really ignores the tremendous improvement in quality that these platforms have achieved over the past tem years.