Fiber-Optic Link Around the Globe

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Fiber-Optic Link Around the Globe
Industry Telecommunication
Founded 1999
Parent Reliance Globalcom

Fiber-Optic Link Around the Globe (FLAG) is a 28,000-kilometer-long optical fiber mostly-submarine communications cable that connects the United Kingdom, Japan, and many places in between. The cable is operated by India's Reliance Globalcom (renamed from Flag Telecom when it became a fully owned subsidiary of Reliance Communications). The system runs from the eastern coast of North America to Japan.[1] Its Europe-Asia segment was the fourth longest cable in the world in 2008.[2]

The Europe-Asia segment was laid by Cable & Wireless Marine in the mid-1990s and was the subject of an article in Wired magazine in December 1996 by Neal Stephenson.[1]

Description[edit]

The FLAG cable system was first placed into commercial service in late 1997.[3] FLAG offered a speed of 10 Gbit/s and uses synchronous digital hierarchy technology. It carries over 120,000 voice channels via 27,000 km of mostly undersea cable. FLAG uses erbium-doped fiber amplifiers and was jointly supplied by AT&T Submarine Systems and KDD-Submarine Cable Systems. Its design, development, installation and service conformed to ISO 9000 quality standards. FLAG provided a link between the European end of high-density transatlantic crossings and the Asian end of the transpacific crossings.[4]

FLAG includes undersea cable segments and two terrestrial crossings. The segments can be either direct point-to-point links or multipoint links which are attained through branching units. At each cable landing point, a FLAG cable station is located. The total route length exceeds 27,000 km and comprises 1,020 km of terrestrial crossings. Approximately 6,600 km of the submerged cable is buried 1 m below the sea bed. Cable burial was performed by either a submersible plough as the cable was laid or jetting the laid cable into the sea bed via remotely operated vehicles (ROVs).[4]

Over several years the route evolved as new branches and feeder systems were considered and realized. FLAG includes two terrestrial crossings, one in Egypt and the other in Thailand. Each of these land crossings is totally duplicated on fully different routes. As a result, any fault within one route will cause automatic protection switching to the other route within a time period of less than 50 ms.[4]

Like other global undersea networks, FLAG uses erbium-doped fibre amplifiers. EDFAs boost the optical signals instead of the optical/electrical conversion which is generally used in regenerative technology. These optical amplifiers use short, gain-specific lengths of fibre which are doped with erbium ions and spliced in-line with the transmission fibre. The signal power is amplified by pumping the erbium-doped fibre (EDF) with 1,480 nm laser light which is attached through an optical coupler. The majority of the repeater components are passive. These include EDF, fused-fibre optical couplers and optical isolators. Active components include laser pump assemblies and associated controls. The total number of components within the repeater is lesser than that of regenerative systems.[4]

The FLAG terrestrial crossings do not contain repeaters for reliability reasons. The terminal stations in land crossings use optical amplifiers, high performance transmitter/receivers and forward error correction to cross the large distances without repeaters. Amplification at the terminal output provides output signal power as high as +17 dBm, and optical amplification at the receiver improves the receiver sensitivity as high as +8 dBm.[4][clarification needed]

The route between Alexandria and Cairo is 223 km long and hence requires remote pumping in order to meet performance requirements. Remotely pumped amplifiers can be regarded as repeaters without active modules. This technology comprises short lengths of EDF spliced into the land cable. The erbium-doped sections are situated within the cable span and are pumped by 1,480 nm pump lasers which are based at the station.[4]

An upgrade to the network was announced in 2006 when the acronym was expanded to "Fibre Loop Across Globe" (FLAG).[5][clarification needed]

Segments and landing points[edit]

Landing points are:

Europe Asia[edit]

FLAG Europe Asia (FEA) was the first segment opened for commercial use on 22 November 1997.[3][6]

Atlantic[edit]

The FLAG Atlantic 1 (FA-1) segment became operational in June 2001.[7] It was constructed as a joint venture between a FLAG Atlantic subsidiary of the parent company FLAG Telecom Holdings, and GTS Transatlantic. Alcatel Submarine Networks laid the undersea portion, and the entire cost was estimated at $1.1 billion.[3][8]

In March 2013 an upgrade for the southerly link was announced to up to 100 Gbit/s with equipment from Ciena.[9]

FLAG Alcatel-Lucent Optical Network (FALCON)[edit]

The FALCON cable system, connecting India and several countries in the Persian Gulf, became operational in September 2006.[10] It has landing points in:[11][12]

There is an additional segment, listed as part of FALCON, but not directly connected. It has landing points in:[11]

In 2006, Kenya Data Networks announced plans for a spur from Yemen to Mombasa.[13]

FLAG North Asia Loop (FNAL) / Tiger[edit]

FNAL became operational in stages, with the final stages completed in 2002.[14] The FNAL landing points are:[15]

West of Mumbai, FLAG has a capacity of 80 Gbit/s.

The segment between Hong Kong and Busan was broken by the 2006 Hengchun earthquake.

Disruptions[edit]

December 2006 and January 2007[edit]

The 2006 Hengchun earthquake occurred on December 26, 2006, off the southwest coast of Taiwan, disrupted Internet services in Asia, affecting many Asian countries. Financial transactions, particularly in the foreign exchange market were seriously affected as well.[16][17] The aforementioned disruption was caused by damage to several submarine communications cables.[18]

January and February 2008[edit]

On January 30, 2008, internet services were widely disrupted in the Middle East and in the Indian subcontinent following damage to the SEA-ME-WE 4 and FLAG cables in the Mediterranean Sea.[19] BBC News Online reported 70% disruption in Egypt and 60% disruption in India[20] Problems were reported in Bahrain, Bangladesh, Kuwait, Pakistan, Qatar, Saudi Arabia and United Arab Emirates.[21] The respective contributions of the two cable systems to this blackout is unclear. Network outage graphs suggest that the two breaks occurred at 0430 and 0800 UTC.[22]

The cause of the damage was not declared by either cable operator, but news sources speculated the damage was caused by a ship's anchor near Alexandria.[20][23] According to the Agence France-Presse, the Kuwaiti government attributed the breaks to "weather conditions and maritime traffic."[24] The New York Times reported that the damage occurred to the two systems separately near Alexandria and near Marseilles.[25] Egypt knew of "no passing ships" near Alexandria which has restricted waters.[26]

One day later, on February 1, 2008, the FALCON cable was also reported cut 56 km off Dubai.[27][28] The first of two repair ships was in place by February 5.[29]

December 2008[edit]

On December 19, 2008 internet services were widely disrupted in the Middle East and in the Indian subcontinent following damage to the SEA-ME-WE 4, SEA-ME-WE 3 and FLAG FEA cables in the Mediterranean Sea.[30]

It is not known what has caused these multiple breaks, however there was seismic activity in the Malta area shortly before the breaks were identified,[30] although it is thought that the damage may be due to a ship's anchor or trawler net.[31]

According to FEA Cable System of Reliance Globalcom, the failure lay between Alexandria and Palermo. Reliance Globalcom completed the repair on the FLAG EUROPE ASIA (FEA) cable on December 29, 2008, at 14:15 GMT. Customer services that were affected due to the cable cut have been restored back normal with the completion of repairs.[32]

August 2009[edit]

Damage to FNAL caused by Typhoon Morakot was reported as affecting internet traffic to China on August 18, 2009.[33]

See also[edit]

Other cable systems following a substantially similar route to FLAG Europe-Asia (FEA) are:

References[edit]

  1. ^ a b Neal Stephenson (December 1996). "Mother Earth Mother Board". Wired (4.12). Retrieved October 5, 2013. 
  2. ^ "The internet's undersea world". The Guardian. February 1, 2008. Retrieved October 5, 2013. 
  3. ^ a b c FLAG Telecom Holdings (May 16, 2000). "Prospectus". US Securities and Exchange Commission. Retrieved 6 October 2013. 
  4. ^ a b c d e f Welsh, Thomas; Smith, Roger; Azami, Haruo; Chrisner, Raymond (February 1996). "The FLAG Cable System". IEEE Communications Magazine 34 (2): 30–35. doi:10.1109/35.481241. 
  5. ^ "Fibre Loop Across Globe". Promotional slides. FLAG Telecom. December 28, 2006. Archived from the original on March 17, 2007. Retrieved October 5, 2013. 
  6. ^ "Coverage Map > Cable Systems > FEA", Reliance Globalcom. Retrieved 15 March 2014.
  7. ^ "FLAG Atlantic-1 Enters Commercial Service", FLAG Telecom, 15 June 2001. Retrieved 15 March 2014.
  8. ^ "Coverage Map > Cable Systems > FA-1", Reliance Globalcom. Retrieved 15 March 2014.
  9. ^ "Reliance Globalcom Upgrades Trans-Atlantic FA-1 South Submarine Network to 100G with Ciena’s GeoMesh". Press release (Ciena). March 14, 2013. Retrieved 6 October 2013. 
  10. ^ "History: 2006", Reliance Globalcom. Retrieved 15 March 2014.
  11. ^ a b "Coverage Map > Cable Systems > FALCON", Reliance Globalcom. Retrieved 15 March 2014.
  12. ^ "FALCON", FLAG Telecom. Retrieved 15 March 2014.
  13. ^ "KDN Pips EASSY To The Post". My Broadband. 25 June 2006. Retrieved 5 October 2013. 
  14. ^ "Flag North Asian Loop Extends Service Into Korea and Japan", Submarine Cable Networks, 21 May 2002. Retrieved 15 March 2014.
  15. ^ "Coverage Map > Cable Systems > FNAL", Reliance Globalcom. Retrieved 15 March 2014.
  16. ^ "網上銀行服務仍「斷纜」". Singtao Daily (星島日報). Archived from the original on 30 December 2006. Retrieved 5 November 2013. 
  17. ^ 韓股匯市受挫港交易無礙 星洲期貨受影響 「彭博」電訊一度中斷, Ming Pao, 2006-12-28 (Chinese)[dead link]
  18. ^ Quakes disrupt Asia communications, CNN, 2006-12-27[dead link]
  19. ^ "Internet failure hits two continents". CNN. Archived from the original on 2008-02-03. 
  20. ^ a b "Severed cables disrupt Internet". BBC News Online (BBC). 2008-01-31. Retrieved 2008-01-31. 
  21. ^ The Associated Press via nytimes.com (February 1, 2008). "Cable Break Causes Wide Internet Outage". The New York Times. Retrieved 2008-02-01. 
  22. ^ Zmijewski, Earl (2008-01-30). "Mediterranean Cable Break". Renesys Blog. Renesys. Archived from the original on February 3, 2008. Retrieved 2008-01-31. 
  23. ^ "Cable damage hits Internet connectivity". The Times of India. 2008-01-31. Retrieved 2008-01-31. 
  24. ^ "Indian outsourcing sector hit by Internet disruption". AFP. 2008-01-31. Retrieved 2008-01-31. 
  25. ^ Timmons, Heather (2008-01-31). "2 Communication Cables in the Mediterranean Are Cut". The New York Times. ISSN 0362-4331. Retrieved 2008-01-31. 
  26. ^ Brauer, David (February 4, 2008). "High-tech mystery: Are terrorists behind recent Internet disruptions?". MinnPost.com (MinnPost). Retrieved 2008-02-04. 
  27. ^ "Update on Submarine Cable Cut". Daily Bulletin (Flag Telecom). February 6, 2008. Archived from the original on February 19, 2008. Retrieved October 5, 2013. 
  28. ^ "Third undersea Internet cable cut in Mideast". CNN. February 1, 2008. Retrieved 2010-05-02. 
  29. ^ "Work begins to repair severed net". BBC News. February 5, 2008. Retrieved October 5, 2013. 
  30. ^ a b "Severed cable disrupts net access". BBC News Online (BBC). 2008-12-19. Retrieved 2008-12-21. 
  31. ^ "Third subsea cable repairs begin". BBC News Online (BBC). 2008-12-23. Retrieved 2008-12-27. 
  32. ^ Reliance Globalcom Cable Update Page
  33. ^ "Damage to undersea cables disrupts int'l telecom services". Xinhua. August 18, 2009. Retrieved October 5, 2013. 

External links[edit]