As the internet rapidly expands with ever more videos, web pages and posts, more ocean-spanning cable lines will be needed to string together this essential global computer network.

In five to seven years, for example, the transatlantic fiber optic cables linking the United States to Europe will run out of capacity.

But a crisis is not looming. Well before the internet slows to a crawl over these increasingly congested pipelines, a company or a consortium of companies will plunk down the funds for more bandwidth across the watery abyss.

"Before we reach the end . . . [we] will install new cables or invent new technologies to squeeze more out of the existing cables," said Tim Stronge, vice president of research for TeleGeography Research, a communications industry research firm.

During a "State of the Global Internet" webinar in late July, Stronge described how a second boom in construction of so-called submarine communications cables is under way.

In recent years, these tubes have progressively hooked up Africa and the Middle East to the World Wide Web and provided more reliable internet access.

Last year, 15 cables were "lit," or entered into service, and a similar number will be lit annually at least through next year. That figure is up from the half-dozen or so lit cables per year in the mid-2000s and vies with the turn-of-the-millennium spike.

These cables are meeting the international demand for bandwidth that TeleGeography estimated will grow about 40 percent each year through 2015. In 2008, roughly 15,000 gigabytes per second flowed over the internet; this year that figure will clear 35,000.

Propelling this explosive growth is broadband penetration into more homes and businesses as well as the continued rise of bandwidth-heavy online video, which accounts for about half of all current internet traffic.

Most of the content on the internet that people in the United States access comes from local or regional servers.

That's because the user experience is better the closer the data is to that person's computer, Stronge explained. Across the Atlantic, for example, there is about an 80 millisecond delay for the data even though it is traveling at light speed.

"If you're just web browsing, [this delay] doesn’t make a big difference," Stronge said. "But if you're playing an online game, that's noticeable, and especially for banks trying to conduct transactions . . . every millisecond counts."

Accordingly, some foreign content gets "cached" locally along with regional data, meaning the data is grabbed from overseas once and then accessed multiple times. (Blue Coat, which sponsored the recent TeleGeography webinar, sells caching services, though Stronge assured that the company exercised no editorial control over the presentation.)

Yet Americans still ping a goodly number of foreign servers, especially in and routed through Europe, as evidenced by the fact that trans-Atlantic internet capacity is twice that of the intra-Asia or trans-Pacific links, according to TeleGeography.

In order to keep the internet humming across the North Atlantic, more modern tubes will be need to go into the water in addition to the ones presently crisscrossing the ocean floor, which were laid mostly between 1998 and 2001.

Extra capacity intentionally built into these fiber optic cables – akin to using the shoulders on a highway as bonus lanes – will soon be used up.

Engineers have also developed new methods to bundle data together into single pulses on optical fibers, which in the highway analogy is roughly like filling the roadway with packed buses rather than cars with a solo occupant.

But as with expanding metropolises, eventually new highways must be built. Though laying a cable about as thick as a fire hose onto the ocean floor for some 3,000 miles (4,828 kilometers) between London and New York City remains expensive, the cost has gone down.

A job that might have cost, say, a billion dollars a decade ago is now in the $4 million to $5 million range now, Stronge said.

But charging for leased bandwidth across cable lines is often not enough to get a return on investment as bandwidth prices continue to fall.

"No one wants to really pay for [new cables]," Stronge said, because "bandwidth is so cheap now it's hard to make your money back."

Nevertheless, a large content-providing company such as Google – which recently invested in its own transpacific cable line – or carriers such as Verizon and AT&T will step up to the plate, Stronge said. The companies might make a deal with European tech companies to foot the bill for re-crossing the Atlantic with fresh cables.

"The international backbones of the internet need to be paid attention to," Stronge said. "In a few years, we will see a company -- at least one – starting the process to build a new [transatlantic] cable."

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