Learn About the Transatlantic Cable

Cables have been used to communicate between the U.S. and Europe for more than a century. The original transatlantic cable was a relatively simple telegraph cable, but laying it across the ocean floor was an immense undertaking. In 1854, entrepreneur Cyrus Field secured a charter for the earliest transatlantic cable. Laying it took four attempts and the help of the U.S. and British navies; efforts lasted between 1857 and 1858, but the cable failed in just a few months. This was a setback, but the seed of the idea changed the course of history.

First Transatlantic Telegraph Cable Laid in 1858
The Great Transatlantic Cable
How the First Transatlantic Cable Was Laid

The first long-term transatlantic telegraph cable was finally laid under Field's direction by 1866, and he was praised around the world for his foresight and dedication to the effort. As crucial as this early cable was, though, it was only a prototype for the effort that would follow more than a century later: the first fiber-optic across the Atlantic, more commonly called "the transatlantic cable" now. This later cable, a "light pipe" using advanced laser technology, represented a quantum leap in speed over the copper cables used for domestic telephones and early data lines.

The Cable that Links the United Kingdom and United States
History of the Transatlantic Optical Cable
Giant Undersea Cable Speeds the Internet by a Split-Second

The first transatlantic fiber-optic cable, called TAT-8, was completed in late December of 1988. It was a massive feat of engineering involving more than 3,000 miles of cable. A joint venture that included AT&T, France Télécom, and British Telecom, it was intended to unite the phone and data networks of these three countries. Most of TAT-8 came in the form of a single "trunk" line that branched when it reached the continental shelf of Great Britain. It was one of the largest telecommunications projects in world history but only one of many modern milestones.

Upgrade of the TAT-14 Cable
The Voyage That Changed The World (PDF)
History of the Atlantic Cable and Undersea Communications

TAT-8 cost more than $330 million and functioned between 1988 and 2002. During its tenure, it dramatically reduced the cost of telephone calls and Internet data exchange between the U.S., U.K., and continental Europe. It inspired a number of other transatlantic cable projects that were backed by major telecom companies, governments, and more. By 2000, consumers were benefiting from a 14th generation of TAT cables with enormous capacity. The mighty Atlantic was no longer a barrier to economic and cultural exchange between nations.

Fiber-Optics and Transatlantic Communication Evolution
Transatlantic Cable Outage Throughout the European Union in 2014

By the early 21st century, a tremendous network of undersea cables had come into being. These cables, many originating in the United States, helped make communication faster and easier than ever before. However, technical problems grew more visible as more people relied on these cables. TAT-8 had several early issues from an unexpected source: sharks. Some experts believe sharks sensed the electrical activity of the cable. Whatever the case, sharks frequently attacked the cable or exhibited unusual, disruptive behavior near it, such as engaging in feeding frenzies. Shark attacks were the main source of serious outages for the cable network for many years.

The Transatlantic Telegraph Cable
The $300 Million Cable That Will Save Milliseconds
The Global Submarine Cable Network

The decade since 2004 has been a time of optimization for the transatlantic cable network. New advances in technology have made the cables less attractive to sea life and less vulnerable to tides. However, the transatlantic cable network is still beset by occasional outages, including one in 2014. Major replacements, such as the one that took place with TAT-8, are rare now: These days, failed segments of the cable can generally be repaired and returned to service in a short time, and redundant lines mean fewer customers are impacted by problems.

Breakthrough in Fiber Optics Could Revolutionize Transatlantic Networks
Understanding How Modern Lasers Made TAT-8 Possible
Background on Laser Breakthroughs Leading to TAT-8

What's next for the transatlantic cable network? It seems likely that fiber-optic cables will remain the preferred medium for transatlantic communication for the foreseeable future. As recently as 2013, University of Southampton researchers were able to develop new fiber-optic cables that could transmit data at 99.7% the speed of light. A relatively recent new cable was laid for the express purpose of ensuring faster access to global financial markets. Every indication is that the undersea network will continue to become faster and more robust, benefiting people worldwide.

History of 21st Century Disruptions in Undersea Cable Lines
Vulnerability of Undersea Internet Cables
The Internet's Undersea World (PDF)