submarine cables

5 Articles

A History Of Internet Outages

July 27, 2024 by 30 Comments

We heard a story that after the recent hurricane, a man noted that while the house was sweltering hot because the power was still out, his kids were more anxious for the internet to come back online. The Internet is practically a basic necessity for most people, but as you may have noticed with the recent CrowdStrike debacle, the Internet isn’t always reliable. Granted, the problem in that case wasn’t the Internet per se, but a problem with many critical hosts that provide services. [Thomas Germain] from the BBC took the opportunity to recall some of the more bizarre reasons we’ve had massive Internet outages in the past.

While teens after a hurricane might miss social media, global outages can be serious business. With 8.5 million computers dead, 911 services went down, medical surgeries were canceled, and — of course — around 46,000 flights were canceled in a single day. We have short memories for these outages, but as [Thomas] points out, this was far from the first massive outage, and many of them have very strange backstories.

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The End Of Landlines?

February 8, 2024 by 94 Comments

Imagine if, somehow, telephones of all kinds had not been invented. Then, this morning, someone entered a big corporation board room and said, “We’d like to string copper wire to every home and business in the country. We’ll get easements and put the wires on poles mostly. But some of them will go underground where we will dig tunnels. Oh, and we will do it in other countries, too, and connect them with giant undersea cables!” We imagine that executive would be looking for a job by lunchtime. Yet, we built that exact system and with far less tech than we have today. But cell phones have replaced the need for copper wire to go everywhere, and now AT&T is petitioning California to let them off the hook — no pun intended — for servicing landlines.

The use of cell phones has dramatically decreased the demand for the POTS or plain old telephone service. Even if you have wired service now, it is more likely fiber optic or, at least, an IP-based network connection that can handle VOIP.

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Loading Coils, The Heaviside Condition, And Pupin Coils

June 19, 2020 by 27 Comments

When we draw schematics, we have the luxury of pretending that wire is free. There are only a few cases where you have to account for the electrical characteristics of wire: when the wire is very long or the frequency on the wire is relatively high.

This became apparent after the first transatlantic cable went into service for telegraph communications. Even though the wire was linear, there was still distortion on the line so severe that dots and dashes would overlap each other. The temporary solution was to limit speeds so slow that operators had trouble sending and receiving at those speeds. How slow? An average character took two minutes to send! That’s not a typo. Two minutes per character. By custom, Morse code assumes a word is five characters, so you could send a word every 10 minutes.

The first transatlantic cable went into service in 1858 and was virtually the moon landing of its day. Frustrated with how slow the communications were, an electrician by the name of Whitehouse decided to crank up the voltage to over 1,000 volts which caused the cable to fail after only three weeks in service. Whoops. Later analysis showed the cable was probably going to fail quickly anyway, but Whitehouse took the public blame.

The wire back then wasn’t as good as what we have today, which led to some of the problems. The insulation was made from multiple coats of a natural latex, gutta percha, which is what dentists use to fill root canals. The jackets were made from tarred hemp and bound with iron wire. There was no way to build an underwater amplifier in 1858, so the cables were just tremendous wires laying on the ocean floor between Newfoundland and Ireland.

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What Lies Beneath: The First Transatlantic Communications Cables

March 18, 2016 by 81 Comments

For some reason, communications and power infrastructure fascinates me, especially the long-haul lines that move power and data over huge distances. There’s something about the scale of these projects that really gets to me, whether it’s a high-tension line marching across the countryside or a cell tower on some remote mountain peak. I recently wrote about infrastructure with a field guide that outlines some of the equipment you can spot on utility poles. But the poles and wires all have to end at the shore. Naturally we have to wonder about the history of the utilities you can’t see – the ones that run under the sea.

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Retrotechtacular: Submarine Cable Splicing Is Serious Business

December 24, 2013 by 50 Comments

Really. As this wonderfully narrated talkie picture from 1939 will attest, keeping even one drop of water from penetrating undersea cables is of the utmost importance.

How do they do it? Many, many layers of protection, including several of jute wrapping. The video centers on splicing a new cable to an existing one in the San Francisco Bay to bring the wonder of telephony to a man-made island created for the Golden Gate International Expo.

The narrator makes these men out to be heroes, and when you see how much lead they came into contact with, you’ll understand what he means. Each of the 1,056 individually insulated wires must be spliced by hand. After that comes a boiling out process in which petrolatum is poured over the splice to remove all moisture. Then, a lead sleeve is pulled over the connections. Molten lead is poured over the sleeve and smoothed out by hand.

At this point, the splice is tested. The sleeve is punctured and nitrogen gas is pumped in at 20psi.  Then comes the most important step: the entire sleeve is painted with soap suds.  Any gas that escapes will make telltale bubbles.

Once they are satisfied with the integrity of the sheath, they wrap the whole thing in what appears to be lead cables and pound them into submission. Surely that would be enough, don’t you think?  Nope.  They weld the cables all around and then apply two coats of tar-treated jute wrapping, which retards saltwater corrosion considerably.

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