Thursday, January 31, 2008

It's been 12 years so it might be $1 million a minute

Wherein I don't have a wherein, just one of my favorite Wired articles


India loses internet access. Kinda amazing how little redundacy some places have. Looking at a 2004 map of undersea cables, India does look underserved.

For further information, there's always Mother Earth Mother Board from the December 1996 issue of Wired magazine. From some guy named Neal Stephenson. I like the way he writes, sure would be nice to see something else by him.

A meandering and extremely entertaining look at the world of deep sea cable operations. In this excerpt he writes about cables being cut:
In 1870, a new cable was laid between England and France, and Napoleon III used it to send a congratulatory message to Queen Victoria. Hours later, a French fisherman hauled the cable up into his boat, identified it as either the tail of a sea monster or a new species of gold-bearing seaweed, and cut off a chunk to take home. Thus was inaugurated an almost incredibly hostile relationship between the cable industry and fishermen. Almost anyone in the cable business will be glad, even eager, to tell you that since 1870 the intelligence and civic responsibility of fisherman have only degraded. Fishermen, for their part, tend to see everyone in the cable business as hard-hearted bluebloods out to screw the common man.

Most of the fishing-related damage is caused by trawlers, which tow big sacklike nets behind them. Trawlers seem designed for the purpose of damaging submarine cables. Various types of hardware are attached to the nets. In some cases, these are otter boards, which act something like rudders to push the net's mouth open. When bottom fish such as halibut are the target, a massive bar is placed across the front of the net with heavy tickler chains dangling from it; these flail against the bottom, stirring up the fish so they will rise up into the maw of the net.

Mere impact can be enough to wreck a cable, if it puts a leak in the insulation. Frequently, though, a net or anchor will snag a cable. If the ship is small and the cable is big, the cable may survive the encounter. There is a type of cable, used up until the advent of optical fiber, called 21-quad, which consists of 21 four-bundle pairs of cable and a coaxial line. It is 15 centimeters in diameter, and a single meter of it weighs 46 kilograms. If a passing ship should happen to catch such a cable with its anchor, it will follow a very simple procedure: abandon it and go buy a new anchor.

But modern cables are much smaller and lighter - a mere 0.85 kg per meter for the unarmored, deep-sea portions of the FLAG cable - and the ships most apt to snag them, trawlers, are getting bigger and more powerful. Now that fishermen have massacred most of the fish in shallower water, they are moving out deeper. Formerly, cable was plowed into the bottom in water shallower than 1,000 meters, which kept it away from the trawlers. Because of recent changes in fishing practices, the figure has been boosted to 2,000 meters. But this means that the old cables are still vulnerable.

When a trawler snags a cable, it will pull it up off the seafloor. How far it gets pulled depends on the weight of the cable, the amount of slack, and the size and horsepower of the ship. Even if the cable is not pulled all the way to the surface, it may get kinked - its minimum bending radius may be violated. If the trawler does succeed in hauling the cable all the way up out of the water, the only way out of the situation, or at least the simplest, is to cut the cable. Dave Handley once did a study of a cable that had been suddenly and mysteriously severed. Hauling up the cut end, he discovered that someone had sliced through it with a cutting torch.


There is also the obvious threat of sabotage by a hostile government, but, surprisingly, this almost never happens. When cypherpunk Doug Barnes was researching his Caribbean project, he spent some time looking into this, because it was exactly the kind of threat he was worried about in the case of a data haven. Somewhat to his own surprise and relief, he concluded that it simply wasn't going to happen. "Cutting a submarine cable," Barnes says, "is like starting a nuclear war. It's easy to do, the results are devastating, and as soon as one country does it, all of the others will retaliate.

"Bert Porter, a Cable & Wireless cable-laying veteran who is now a freelancer, was beachmaster for the Tong Fuk lay. He was on a ship that laid a cable from Hong Kong to Singapore during the late 1960s. Along the way they passed south of Lan Tao Island, and so the view from Tong Fuk Beach is a trip down memory lane for him. "The repeater spacing was about 18 miles," he says, "and so the first repeater went into the water right out there. Then, a few days later, the cable suddenly tested broken." In other words, the shore station in Hong Kong had lost contact with the equipment on board Porter's cable ship. In such cases it's easy to figure out roughly where the break occurred - by measuring the resistance in the cable's conductors - and they knew it had to be somewhere in the vicinity of the first repeater. "So we backtracked, pulling up cable, and when we got right out there," he waves his hand out over the bay, "we discovered that the repeater had simply been chopped out." He holds his hands up parallel, like twin blades. "Apparently the Chinese were curious about our repeaters, so they thought they'd come out and get one."


As the capacity of optical fibers climbs, so does the economic damage caused when the cable is severed. FLAG makes its money by selling capacity to long-distance carriers, who turn around and resell it to end users at rates that are increasingly determined by what the market will bear. If FLAG gets chopped, no calls get through. The carriers' phone calls get routed to FLAG's competitors (other cables or satellites), and FLAG loses the revenue represented by those calls until the cable is repaired. The amount of revenue it loses is a function of how many calls the cable is physically capable of carrying, how close to capacity the cable is running, and what prices the market will bear for calls on the broken cable segment. In other words, a break between Dubai and Bombay might cost FLAG more in revenue loss than a break between Korea and Japan if calls between Dubai and Bombay cost more.

The rule of thumb for calculating revenue loss works like this: for every penny per minute that the long distance market will bear on a particular route, the loss of revenue, should FLAG be severed on that route, is about $3,000 a minute. So if calls on that route are a dime a minute, the damage is $30,000 a minute, and if calls are a dollar a minute, the damage is almost a third of a million dollars for every minute the cable is down. Upcoming advances in fiber bandwidth may push this figure, for some cables, past the million-dollar-a-minute mark.

Clearly, submarine cable repair is a good business to be in. Cable repair ships are standing by in ports all over the world, on 24-hour call, waiting for a break to happen somewhere in their neighborhood. They are called agreement ships. Sometimes, when nothing else is going on, they will go out and pull up old abandoned cables. The stated reason for this is that the old cables present a hazard to other ships. However, if you do so much as raise an eyebrow at this explanation, any cable man will be happy to tell you the real reason: whenever a fisherman snags his net on anything - a rock, a wreck, or even a figment of his imagination - he will go out and sue whatever company happens to have a cable in that general vicinity. The cable companies are waiting eagerly for the day when a fisherman goes into court claiming to have snagged his nets on a cable, only to be informed that the cable was pulled up by an agreement ship years before.

0 Comments:

Post a Comment

Links to this post:

Create a Link

<< Home