Transatlantic Optical Cable

On 14 December 1988, TAT-8, the first transatlantic optical fiber cable system was completed across the Atlantic. The 3,148 mile line was capable of handling 40,000 telephone calls simultaneously.

TAT-8 was built as a joint venture of AT&T, France Télécom, and British Telecom to connect the communications systems of France, Britain, and the United States. It could serve all three countries with a single line through the creation of an underwater branching unit on the continental shelf on the coast of Great Britain. Built at the cost of $335 million and operating from 1988 to 2002, TAT-8 revolutionized communications by employing two working pairs of optical fibers, rather than traditional copper coaxial cables, to carry voice and data across the ocean. Its capacity lowered the cost of communications across the globe and provided indispensable infrastructure for the development of the Internet.

AT&T encountered a surprising problem with fiberoptic cable when it laid experimental lines near the Canary Islands. Apparently attracted to the magnetic fields generated by the cable, sharks were chewing through the plastic covering on the lines and electrocuting themselves in the process.

TAT-8’s dominance in transatlantic communications was short-lived. In 1989, the first privately financed transatlantic fiberoptic cable, the PTAT-1, was completed, breaking the communications monopoly held by AT&T and British Telecom. Subsequent fiberoptic cables offered far greater capacity. TAT-8 carried 560 Mb/s, while PTAT-1 moved data at 1.26 Gb/s. The fourteenth-generation TAT-14, completed in 2000, had a capacity of 10 GB/s.