Global Submarine Cable Network

Global Submarine Cable Network

Source: Dataset encoded by Greg Mahlknecht.

The setting of the first submarine cables took place in the second half of the 19th century, notably with the laying of the first successful transatlantic cable in 1866. By 1900 a global telegraphic cable network was established with transpacific connections completed in 1902. By 1956 the telegraphic system switched to telephonic cables with the first transatlantic telephone line (TAT-1). However, since their inception, submarine cables were facing a bandwidth problem, making transoceanic communication expensive and mostly used for business or government transactions. As it was the case in the 19th century, submarine cables are laid by ships and are thus capital intensive projects.

The development of fiber optic transmission technology provided a substantial impetus in the setting of a global telecommunication network since it permitted significantly higher bandwidth and less signal degradation. Throughput of hundreds of gigabytes of information per second became possible. The first transatlantic fiber-optic cable (TAT-8) was laid in 1988. Over the years, fiber optic cables were laid across the world, connecting economies and societies increasingly dependent on telecommunications (see above map). The internet could not have existed otherwise. While initial submarine cables were laid on a point to point basis, technical advances permitted branching so that one cable could service a sequence of hubs (e.g. Africa and Latin America).

The global network is designed for redundancy. Several cables are laid in parallel for major connections (transatlantic and transpacific), implying that a failure in one cable can mitigate by rerouting traffic to the others. In recent years, Pacific Asia has seen significant submarine cable laying activities supporting its economic development. In 2012, a new route for submarine cable was established with the setting of the first Arctic cables between London and Tokyo through the Northwest Passage. Besides, to provide additional redundancy to the global telecommunication network, it shaves about 60 milliseconds in the connection speed. Through lower latency (delay) levels, this improves bandwidth-intensive telecommunications between Europe and Pacific Asia, such as financial transactions and videoconferencing. Another trend concerns the setting of large data centers in northern areas, namely Scandinavian countries. They benefit from cooler temperatures, which confers savings as data centers generate a lot of heat. Because of hydroelectric potential, Nordic countries generally have lower electricity costs.