A submarine communications cable is a cable laid beneath the sea to carry telecommunications between countries. The first submarine communications cables carried telegraphy traffic. Subsequent generations of cables carried first telephony traffic, then data communications traffic. All modern cables use fiber optic technology to carry digital payloads, which are then used to carry telephone traffic as well as Internet and private data traffic.

As of 2002, submarine cables link all the world's continents except Antarctica.

• Timeline of Submarine Communications Cables, 1850-2004 (http://www.atlantic-cable.com/Cables/CableTimeLine/index.htm)

It is designed to factor out general communications cable issues from transatlantic / telephone / telegraph special cases

History of submarine communications cables

The first submarine communications cable was a telegraph cable laid between England and France in August 1850 by the Anglo-French Telegraph Company. In 1852 a link laid by the Submarine Telegraph Company linked London to Paris for the first time.

The first transatlantic telegraph cable was laid in 1858 (Cyrus Field). It only operated for a month. Attempts in 1865 and 1866 were more successful but although a telephone cable was discussed from the 1920s it needed a number of technological advances that did not arrive until the 1940s to be practical.

In 1942, Siemens Brothers, in conjunction with the British National Physical Laboratory adapted submarine communications cable technology to create the World's first submarine oil pipeline in Operation Pluto.

• blowing up the first transatlantic cable
• Lord Kelvin and the mirror galvanometer

TAT-1 (Transatlantic No. 1) was the first transatlantic telephone cable system. It was laid between Gallanach Bay, near Oban, Scotland and Clarenville, Newfoundland between 1955 and 1956. It was inaugurated on September 25 1956, initially carrying 36 telephone channels.

• British Pacific Cable: October 31, 1902

Technology of submarine communications cables

• electromagnetic issues
• mirror galvanometer
• coaxial cable
• frequency division multiplexing
• reliability
• repeaters
• power distribution for repeaters
• fiber optics
• optical repeaters, Erbium-doped fiber amplifier
• self-healing ring
• SONET
• wavelength division multiplexing

to be written

Economics of submarine communications cables

• national telco partnerships
• opening to third parties
• indefeasible rights of use (IRUs)
• venture capital
• boom and bust
• FLAG, Project Oxygen
• exponential rise in capacity over time makes value of IRUs implode

to be written

Owners and operators of submarine communications cables

to be written

Owners and operators of cable-laying ships

• TYCO

to be written

See also:

• Communications satellite
• Internet
• transatlantic telegraph cable
• transatlantic telephone cable
• optical fiber
• Public switched telephone network

External links:

• http://gallery.colofinder.net/cableships -- Photo gallery of cable laying ships and other equipment
• http://www.atlantic-cable.com/Article/WireRope/wirerope.htm
• http://www.iscpc.org/ - The International Cable Protection Committee -- includes a register of submarine cables worldwide (though not always updated as often as one might hope)
• Cableships of the World (http://www.iscpc.org/information/ships.htm)
• FLAG telecom network summary (http://www.flagtelecom.com/network/network_chart.htm)
• A short history of telegraphy (http://www.samhallas.co.uk/telhist1/telehist.htm)
• An Oversimplified Overview of Undersea Cable Systems (http://davidw.home.cern.ch/davidw/public/SubCables.html)