If you're reading this outside continental North America, you almost certainly used a submarine cable to get it.

With the exception of Antarctica, which relies on satellites, overseas internet, phone and fax communication almost exclusively run on undersea fibre optic cables. And those cables cross the seas all over the map.

Telecommunications market research and consulting firm TeleGeography has an interactive map on their website showing 343 submarine cables, in service and planned. And the number keeps growing.

The map lists 12 cables as ready for service in 2014 and another eight cables in 2015.

This year, TeleGeography began offering a printed map of submarine cables designed in the map style of the Age of Discovery, and in homage to those maps, it includes "ornate illustrations of mythical sea monsters."

Vladimir Putin navy ceremony

Russian President Vladimir Putin attends a welcome ceremony in front of the 'Vice-Admiral Kulakov' large anti-submarine ship in the Black Sea port of Novorossiysk, Russia, Sept. 23 2014. (Mikhail Klimentyev/Ria Novosti/EPA)

A story on Sunday from the New York Times makes it sound like the next edition of the map should also add ornate illustrations of Russian submarines and spy ships.

According to the Times, their military and intelligence sources are saying "that from the North Sea to Northeast Asia and even in waters closer to American shores, they are monitoring significantly increased Russian activity along the known routes of the cables."

The speculation in the Times centres on a strengthened Russian navy "hunting for new Western vulnerabilities."

Content companies the new big consumers

Here are some numbers that may make you wonder whether this could have something to do with Google, Facebook and Microsoft.

In 2014, the bandwidth used by those companies and other content providers themselves exceeded other internet bandwidth use on the transatlantic cables for the first time, TeleGeography's statistics show. Last year, 56 per cent of bandwidth demand on that route was used by private networks. Switched voice communication uses less than one per cent.

Subsea cable Cuba 2011

Cuban workers drag an undersea fibre optic cable in Santiago de Cuba, Cuba, on Feb. 9, 2011. The cable connects with Venezuela. (Miguel Rubiera/EPA)

Content providers such as Google, Facebook and Microsoft helped increase global bandwidth demand by 44 per cent last year. Capacity is keeping pace, though, more than doubling between 2012 and 2014.

There's a lot of spare room on the cables, with all regions using 25 per cent or less of their capacity.

Demand is growing fastest in Africa, Asia and the Middle East, but that's also where the bulk of the money invested in new submarine cables goes, with Latin America expected to soon follow.

The next development may be content providers building their own submarine cable systems, TeleGeography reports. If they do, they will need to figure out how to deal with cable breaks.

Frequent cable breaks

TeleGeography researcher Tim Stronge says a cable break happens so often, about twice a week, that it's "a ho-hum event" — but an expensive one.

"They break so frequently, there's a whole mini-industry dedicated to repairing them," he told CBC News, speaking from Washington, D.C.  Fleets of ships and their crews are kept on standby, dedicated exclusively to repairing undersea fibre optic cables.

"The industry as a whole is well-equipped to handle cable failures," Stronge says.

The breaks may be frequent, but don't go blaming them for your connections problems, he advises. The cable system, like the internet, is designed for resilience, so when one cable breaks, transmissions shift to other cables.

He does concede that if a company purchased capacity on just one cable and that happens to be the one that breaks, it could take them a bit of time to acquire capacity on other cables.

About two-thirds of the breaks are caused by anchors or fishing trawlers, the rest mostly by undersea earthquakes and volcanoes and other natural events. The tsunami that hit Japan in 2011 broke about half the cables connecting the country.

Protecting the cables

Some countries require vessels of a certain size to have a transponder so they will be detected, and warned, when they are over a fibre optic cable. Telecoms and governments use satellite technology to monitor the areas near cables. The telecom industry also provides the fishing industry with maps showing cable locations, so fishing boats can avoid them.

Tim Stronge

Tim Stronge, vice president of research at TeleGeography, says there are about 100 submarine cable breaks per year. (Telegeography/NANOG)

In other words, cable locations aren't a secret. Stronge says that's important, because with so many accidents already, the rate would be way higher if they were secret. "Fishermen would be breaking them all the time."

When they are on the deep sea floor, the fibre optic cables have barely any protection, just a plastic sheath wrapping the fibres and the copper tubing used to conduct electricity to power equipment needed to make long-distance cables run.

Stronge says when it comes to cutting them, "we're talking a garden hose, essentially," but there's so little human activity in these areas, cuts rarely happen.

In more shallow waters the cables have more protection, steel wrapping that makes them like steel ropes. Close to the beach they are slightly buried under the sea floor.

Stronge says there have been only a handful of incidents of deliberate sabotage, usually  thieves after copper wire accidentally pulling up fibre optic cable, "who thought they were getting something worthwhile that wasn't."

What if?

What if someone wanted to cut transatlantic telecommunication?

Fifteen cables handle that traffic, and ships are out in the Atlantic right now laying the sixteenth. So 16 cables would have to be cut.

Stronge says such "very widespread and co-ordinated attacks would be very difficult to pull off and very expensive to do, it would require multiple ships," since the undersea cables don't follow just one path.

And such a hypothetical attack could be construed as an act of war, he says. "If the Russians deliberately attacked all 16 cables across the Atlantic simultaneously, then I suspect that we have far greater problems on hand than internet outage."

And it wouldn't be that big a deal for North American internet users, in any case. Many of the popular European websites are hosted in North America and domestic communications would continue to operate.

Users in Europe, Africa and the Middle East, however, would be affected, and so would overseas telephone calls and the transatlantic networks that connect governments.

Varshavyanka class submarine

The crew of the Varshavyanka class submarine take part at the Victory Day parade in Vladivostok, Russia, May 9. (RIA Novosti/Reuters)

Russia's undersea cables

The TeleGeography submarine cable map shows only six cables connect to Russia, while seven connect or will soon connect to Canada, by comparison. Stronge says Russia isn't heavily dependent on international submarine cables, and in that regard, they are an island within themselves. They do use cables in the Baltic Sea and a connection to Japan, but they meet a lot of their external requirements through land-line connections to Western Europe. 

Writing about the New York Times's story, the Washington Post comments that "the Russians appear to be taking a page out of the book that the U.S. Navy and the NSA wrote in the 1970s in a series of undersea wiretapping missions that became known as Operation Ivy Bells."

The operation started in 1972, targeting information about Russian ballistic missile submarine deployments and strategy. The wiretapping didn't cut the cables but wrapped them in order to glean the Russian communications.

TeleGeography map Russia

This close-up from TeleGeography's submarine cable map shows Russia with just six cable connections. (Telegeography)