Meta (formerly Facebook) plans to build the world's longest undersea cable that will be longer than the Earth is round. The high-capacity, fiber-optic cable that will link five continents will span a fantastic 31,000 miles (50,000 km) – for reference, the circumference of the Earth is 24,901 miles (40,075 km).
Undersea cables are one of those technologies that most of us are probably unaware of or assume to be some old-fashioned marginal holdover from the Victorian era. In fact, our global digital culture is utterly dependent on a vast network of cables running across every sea that are far from being marginal, carrying over 95% of all the telecommunication data between continents.
When the first successful transatlantic cable opened for business on August 16, 1858, it was something of a nine-day wonder. Though it could only carry about one byte of Morse code every two minutes, it heralded a new age. Oceans that once took weeks or months to span, were jumped over in seconds by messages tapped out on a telegraph key.
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In less than 20 years, this single cable became an increasingly large and increasingly important network, with Britain linking its empire from London to India and beyond with cables under its sole control for security reasons.
Today, there are over 600 undersea cables linking the world together and maps of them look like some global underground railway network. Compared to them, the satellite links are almost an afterthought when it comes to sheer traffic flow.
This is one reason why events of recent years have gained the attention of the world's government as Baltic Sea cables have been repeatedly cut under suspicious circumstances – especially around Finland and Sweden.
The early undersea cables were made of copper, though most of the thickness was made of a wrapping of steel cable for armor protection as well as layers of waterproof materials. Today, the cables use glass fibers that carry laser impulses instead of electricity.
According to Meta, the new multi-billion dollar cable will link the USA, India, Brazil, South Africa, and Australia and form a new backbone for the world's data system. Aside from its length, the new cable will have a much larger capacity, with 24 fiber pairs, making it the largest of its kind ever built. It will be laid on the seabed to a depth of up to 4.3 miles (7 km), with some lengths in shallow waters being buried to protect against accidental or intentional interference.
Source: Meta