Transatlantic communications cable

A transatlantic telecommunications cable is a submarine communications cable connecting one side of the Atlantic Ocean to the other.

History

When the first transatlantic telegraph cable was laid in 1858 by businessman Cyrus West Field, it operated for only three weeks; subsequent attempts in 1865 and 1866 were more successful. Although a telephone cable was discussed starting in the 1920s, to be practical it needed a number of technological advances which did not arrive until the 1940s. Starting in 1927, transatlantic telephone service was radio-based.[1]

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 by the cable ship Monarch.[2] It was inaugurated on September 25, 1956, initially carrying 36 telephone channels. In the first 24 hours of public service there were 588 London–U.S. calls and 119 from London to Canada. The capacity of the cable was soon increased to 48 channels. TAT-1 was finally retired in 1978. Later coaxial cables, installed through the 1970s, used transistors and had higher bandwidth.

Current technology

All cables presently in service use fiber optic technology. Many cables terminate in Newfoundland and Ireland, which lie on the great circle route (the shortest route) from London, UK to New York City, USA.

There have been a succession of newer transatlantic cable systems. All recent systems have used fiber optic transmission, and a self-healing ring topology. Late in the 20th century, communications satellites lost most of their North Atlantic telephone traffic to these low cost, high capacity, low latency cables. This advantage only increases over time as tighter cables provide higher speed – the 2012 generation of cables drop the transatlantic latency to under 60 milliseconds, according to Hibernia Atlantic, deploying such a cable that year.[3][4]

Some new cables are being announced on the South Atlantic: SACS(South Atlantic Cable System)[5] and SAex(South Atlantic Express) [6]

TAT cable routes

The TAT series of cables constitute a large percentage of all North Atlantic cables. All TAT cables are joint ventures between a number of telecommunications companies, e.g. British Telecom. CANTAT cables terminate in Canada rather than in the USA.

NameIn serviceTypeInitial channelsFinal channelsWestern endEastern end
TAT-11956–1978Galvanic3648NewfoundlandUnited Kingdom
TAT-21959–1982Galvanic4872NewfoundlandFrance
TAT-31963–1986Galvanic138276New JerseyUnited Kingdom
TAT-41965–1987Galvanic138345New JerseyFrance
TAT-51970–1993Galvanic8452,112Rhode IslandSpain
TAT-61976–1994Galvanic4,00010,000Rhode IslandFrance
TAT-71978–1994Galvanic4,00010,500New JerseyUnited Kingdom
TAT-81988–2002Fiber-optic40,000–USAUnited Kingdom, France
TAT-91992–2004Fiber-optic80,000–USA, Nova ScotiaSpain, France, United Kingdom
TAT-101992–2003Fiber-optic2 × 565 Mbit/s–USAGermany
TAT-111993–2003Fiber-optic2 × 565 Mbit/s–USAFrance
TAT-12/131996–2008Fiber-optic12 × 2.5 Gbit/s–USA × 2United Kingdom, France
TAT-142001–Fiber-optic3.2 Tbit/s–USA × 2United Kingdom, France, Netherlands, Germany, Denmark
CANTAT-11961–1986Galvanic80–NewfoundlandUnited Kingdom
CANTAT-21974–1992Galvanic1,840–Nova ScotiaUnited Kingdom
CANTAT-31994–2010Fiber-optic2 × 2.5 Gbit/sNova ScotiaIceland, Faroe Islands, United Kingdom, Denmark, Germany
PTAT-11989–2004Fiber-optic3 × 140 Mbit/s?New Jersey & BermudaIreland & United Kingdom

Private cable routes

There are a number of private non-TAT cables.

Cable name Date(s) Nominal capacity Latency (ms) Landings Owner
Gemini (decommissioned) 1998 Under 100 ms Vodafone (originally Cable & Wireless)
Apollo 2002 3.2 Tbit/s Under 100 ms Vodafone/Alcatel-Lucent (originally Cable & Wireless)[7]
AC-1 1998 120 Gbit/s 65 ms[4] Level 3 Communications (originally Global Crossing)
Yellow/AC-2 2000 640 Gbit/s Under 100 ms Level 3 Communications
FLAG Atlantic 2000 Under 100 ms Reliance Communications
VSNL Transatlantic 2001 5.1 Tbit/s Under 100 ms Sold by Tyco to VSNL in 2005
Hibernia Atlantic 2001 320 Gbit/s, upgraded to 10.16 Tbit/s[8] Under 70 ms CVC Acquisition Company
Emerald Express 2014 (scheduled)[9] 4 × 10 Tbit/s (four strand 100 × 100 Gbit/s) 54 ms Moncton; St. John's; Grindavík, Iceland; Belfast; Dublin; Shirley, New York Emerald Atlantis
Hibernia Atlantic 2012 Unknown (four strand) 59 ms[4] Herring Cove (near Halifax, Canada) CVC Acquisition Company

South Atlantic cable routes

Cable name Date(s) Landing Owner
SACS 2016 Luanda; Fortaleza Angola Cables
SAex 2017 Mtunzini; Yzerfontein; Saint Helena; Fortaleza SimplCom South Africa

See also

References

  1. ↑ Short-Wave System for Transatlantic Telephony, by Polkinghorn and Schlaack BSTJ, 1935
  2. ↑ "Being First Telephone Cable to Connect Hemispheres" Popular Mechanics, March 1954, p. 114.
  3. ↑ Post (October 9, 2011). "Building Networks for High-Speed Stock Trading - WSJ.com". Online.wsj.com. Retrieved September 18, 2013.
  4. ↑ 4.0 4.1 4.2 "The $300m cable that will save traders milliseconds". The Daily Telegraph (London). September 11, 2011. Retrieved September 18, 2013.
  5. ↑ http://www.nec.com/en/press/201411/global_20141104_04.html
  6. ↑ http://www.techcentral.co.za/16tbits-saex-cable-deal-signed/35811/
  7. ↑ "Submarine Cable Actions Taken PN". FCC. October 4, 2012.
  8. ↑ "Hibernia Offers Cross-Atlantic 40G". Light Reading. August 13, 2009.
  9. ↑ "About Us | Emerald Networks". Emerald Networks. February 14, 2013.

External links