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Beware the Ides of March: Subsea Cable Cut Trend Continues

Earlier this month, the International Cable Protection Committee, a submarine cable advisory group, held their annual plenary in Dubai. One question that they could have considered is: Why do so many submarine cables get cut in the February/March timeframe? In this blog, we’ll look back at the last three years and the submarine cable industry’s own version of March Madness.


Two years ago in February 2012, we saw a rash of closely-timed submarine cable cuts, causing Internet disruptions extending into March. In one incident, three cables were simultaneously severed in the Red Sea on February 17th, and then a fourth was damaged on the 25th off the coast of Kenya. The fourth cable was the TEAMS (The East African Marine System) cable systems, which runs from Mombasa to Fujairah, UAE.

We detailed the impact of the TEAMS cable break here, noting the resilience of many East African providers, who had purchased redundant capacity on the other two East African submarine cables: EASSy and SEACOM. The TEAMS cable would experience a second cut just weeks after it was repaired, which led TEAMS to threaten a lawsuit against the Kenya Ports Authority (KPA) over the repeated damage caused by ships passing through its jurisdiction. teams

We also detailed the loss and subsequent return of Sea-Me-We 3 (one of those cut in the Red Sea on the 17th) on Omantel‘s service, where we stated that the “new EPEG terrestrial cable through Russia and Iran cannot come fast enough for Oman”. But then the Sea-Me-We 4 outage in March the following year seemed to trigger the early activation of the EPEG cable, a system designed to provide service throughout the Middle East via Iran.


In March of 2013, we observed a rash of submarine cable cuts culminating in a bizarre incident on March 27th in which the Egyptian Navy claimed to have caught three scuba divers off the coast of Alexandria trying to blow up a submarine cable with explosives. According to the article in the Guardian, the Egyptian Navy “had no explanation of who they were working for, where they came from or why they would want to disrupt Egypt’s internet communications.”

That same morning, Sea-Me-We 4 suffered a break, which we detailed in a blog post here. This cable break, combined with breaks just days prior, led to severe international connectivity problems from East Africa to the Middle East and South Asia, where Pakistan was already reeling from the loss of the IMEWE on March 8th. The story of the Egyptian divers ultimately disappeared from the news forever and has never been fully explained. divers

Only days prior, on March 22nd, an oil tanker (B ELEPHANT) commanded by Captain Syed Irfan Haq, a Pakistani national, dropped anchor off the coast of Egypt and severed both the EIG and TE-North submarine cables. Last month, Captain Syed was convicted of negligence in an Egyptian court and received a suspended prison sentence.


So that brief recap brings us to this year. While there have been a few cable stories in the past month, none have been nearly as sensational as scuba-diving saboteurs getting pulled out of the Mediterranean. Regardless, here’s a run-down of some of the submarine cable outages of this past March.


Last week at 20:29 UTC on March 23rd, east Asian submarine cable APCN-2 suffered an outage, causing increased latencies around East Asia. Eastern Telecom of the Philippines was hit especially hard, as can be seen in the latency charts below.

latencies_icn_9658_bgp02.tyo1_s latencies_icn_9658_vps01.pvg2_s


The week prior, the Middle East submarine cable FLAG-FALCON suffered a break on the same day its parent company, Global Cloud Xchange, which recently changed its name from Reliance Communications. This cable disruption kept the company from providing Internet transit for several of its customers in the Middle East for about 30 hours.

From routing, we can see the impact on customers such as YemenNet (AS12486) and Bahraini incumbent Batelco (AS5416).

falcon_yemennet falcon_batelco

From a latency standpoint, we can see impacts on Gulfnet Kuwait and Kanar Telecom of Sudan below.

latencies_6762_3225_AllSources_b_s latencies_2914_33788_AllSources_b_s


The East Africa Submarine SYstem (EASSy) also experienced a cut on 13 March impacted Vodafone Tanzania, which had to shift traffic to the SEACOM cable.

A couple of days later, segments of the EASSy cable were down again for several hours, either for additional repairs or for work towards their 100 Gbps upgrade. In any case, Telma of Madagascar (pictured lower left) had to shift traffic to Gilat satellite (in red) as well as Orange Madagascar (in cyan) over the new LION-2 submarine cable. The island nation of Comoros was offline as it is completely dependent on the EASSy cable.

latencies_37054_AllSources_b_s latencies_36939_AllSources_b_s

FOG cable cut

At 3:30 UTC on 2 March, the Fiber Optic Gulf (FOG) submarine cable suffered a break and wasn’t returned to service until the end of the month. The cable break impacted Qatar Telecom (a.k.a. Ooredoo) service around the Gulf. Below are examples of impacted providers in Bahrain and Kuwait.

35457 43852

Asia-America Gateway (AAG) Repairs

The spur of the AAG submarine cable serving Vietnam suffered a cut on 21 December 2013. It wasn’t repaired until January 5th — more than two weeks later. Then earlier this month, the landing station was powered down for additional repairs lasting two weeks. While this cable outage was part of a planned repair, it still had a significant impact on latencies into Vietnam. In the graphic on the lower left, a screenshot from Renesys Internet Intelligence (RII) clearly shows the impact on latencies from Tokyo to Vietnam. Without the AAG cable, traffic from Tokyo had to hair-pin off the west coast of the United States to reach VNPT via an alternate submarine cable.



Although the Greenland submarine cable cuts didn’t take place this month, a lawsuit resulting from them did.

On March 7th, TELE Greenland brought forth a lawsuit in Canadian federal court in Halifax to force Canadian Department of Fisheries and Oceans (DFO) to reveal which fishing trawler cut its submarine cables not once but twice – on May 3rd and then again on May 25th of last year. Although the DFO tracks the location of such vessels, it has so far has refused to provide this information to TELE Greenland. In the plot below, we can see TELE Greenland’s loss of Canadian provider Eastlink (AS11260) twice in May. Each time it shifted its routes to Tele Danmark (TDC) (AS3292). telegreenland

The lawsuit requests names of the ships located in the vicinity of the cuts “between 2:20 UTC, May 1, 2013 until 3:20 UTC, May 3, 2013 inclusive” and “between 2:20 UTC, May 24, 2013 until 3:20 UTC, May 25, 2013 inclusive”. In fact, based on the timing of the disconnection of Eastlink and TELE Greenland in BGP routing data, we can see that the cuts took place at 3:33 UTC on May 3rd and 2:31 UTC on May 25th — the second one just 4 days after being restored at 14:48 UTC on May 21st.

Latencies from many European cities were unaffected by the cable cuts as they already used TDC to reach Greenland from the east. However, in a few interesting cases (including Vienna, Austria), latencies improved (got lower) as a result of the cut by eliminating hair-pinning through the United States. Latencies from the US increased as Internet traffic bound for Greenland could no longer traverse the direct route through eastern Canada and instead had to bounce off Europe. Latencies from New York and Vienna, Austria to TELE Greenland during this time period are shown below.

latencies_1395775132_vps01.nyc1_s latencies_1395776985_vps01.vie1_s


Truth be told, submarine cable cuts occur year around. One need only scroll through our twitter feed to find plenty of examples. They range from the bombing of the landing station for Silphium cable in Libya last September to the SMW3 cut off the coast of Perth, Australia last January. But in recent years, some of the highest profile incidents have occurred around this time of year. On the bright side, March 2014 is almost over.


Finally, it is with heavy hearts that we would like to extend our condolences to the families of the passengers and crew of Malaysia Flight MH370. On board that flight was Hualian (Happy) Zhang, the VP of Network Planning for China Telecom Global. I met Ms. Zhang last fall in Singapore when she was a fellow speaker at Submarine Networks World 2013. Ms. Zhang was reportedly returning from Kuala Lumpur after participating in the C&MA (construction and maintenance agreement) signing for Sea-Me-We 5, a submarine cable planned to run from Asia to Europe. Ms. Zhang’s untimely death is a tremendous loss for the submarine cable community and the world of telecommunications.

Update: APCN-2 restored on 4 April.

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Doug Madory
Whois: Doug Madory

Doug Madory is a Director of Internet Analysis at Oracle Dyn where he works on Internet infrastructure analysis projects. Doug has a special interest in mapping the logical Internet to the physical lines that connect it together, with a focus on submarine cables.

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