Friday, March 25, 2011

Quake damaged cables slow Asia's net

The magnitude 9 earthquake which struck off the coast of Japan two weeks ago caused widespread destruction which has yet to be assessed properly. The tsunami which followed washed away entire towns and displaced hundreds of thousands of people. The death toll has risen to nearly 10,000 but there is at least another 13,000 missing and unaccounted for. Meanwhile engineers are battling to make safe the Fukushima nuclear reactor which was severely damaged and issued radioactive material over a large part of Japan, the risks of which are still being established. But the damage went beyond the shores of Japan with undersea telecommunications cables being severed.

The Internet is, by its very structure, fairly robust and routes traffic through different nodes should others fail. But much of the infrastructure is old and when major lines go down other parts of the system cannot cope with the extra traffic. It has meant that many parts of Asia have seen extremely slow Internet connection over the past two weeks.

Internet disruption

In Beijing and other cities across China many people began to see slow connections a few days after the quake. But the connection was not immediately made to the disaster which struck Japan. Chinese authorities often restrict the Internet, slowing traffic and blocking websites, so a reduction in the speed of the Internet was seen by some as a reaction to recent calls for a so-called Jasmine Revolution in China.

Internet services within China seemed to be less affected, but accessing websites based outside the country were fast becoming extremely unreliable. Expats in particular were beginning to notice problems. Comments on Twitter began to appear with users becoming exasperated. "Chinese Internet is slow like molasses in Alaska. Worried that I'll not even get a radio feed for tomorrow's Timbers FC match," one Twitter user observed around a week after the quake. With apparent blocks of GMail by the Chinese government, most people assumed that the slow Internet was due to government action. Using a VPN, which directs traffic to foreign servers, did not help. VPNs have been targeted by Chinese authorities and so this was also assumed to be a cause of the problem. But it has gradually become clear that the slow Internet has more to do with damage to undersea cables.

Repairs underway

There have been relatively few reports concerning the damage inflicted on the Internet by the earthquake. But on Thursday 24th March The Shanghai Daily reported that the problems seen over the last two weeks were due, at least in part, by the damage done to telecommunications cables. The paper said it may take up to 45 days for services to return to normal however.

A joint repair operation is under way to fix submarine cables a Chinese cable company said. The team consisting of a repair ship carrying 50 Chinese and foreign technicians left Shanghai port on Thursday for waters near Taiwan. They will attempt to reconnect three of a dozen cables on the seafloor using a robot. Other damaged cables will be repaired at the same time by teams from South Korea and Japan.

The repair work has been delayed due to concerns over aftershocks, the cable company said. China's telecommunication authority said only a small number of users on the mainland were still affected by the damage. But the experience described by many users across China tells a different story.

According to the KDDI, a Japanese telecommunications firm, the operation to reconnect the cables will not be straightforward. Robots capable of diving to 2,500m have been deployed in order to fix the cables but it might take months to complete. Robots have never been used for repairing cables before, only deploying them, so the challenge is much greater.

Extensive damage

It is thought that over 150,000 circuits are currently offline, and mobile networks have also suffered in these cuts. Pacnet, a Hong Kong-based cable-network operator, estimates about half the cables running across the Pacific are damaged thus affecting connections to the US. Because of redundancy that has been put in place, connectivity is possible but in a degraded state which for many means a much slower connection.

Many telecom operators and users were reporting some disruptions to the Internet as early as Monday 14th March. Partial restoration of services was accomplished by re-routing traffic over undamaged cables and via satellites.

About half of the existing cables running across the Pacific are damaged and "a lot of people are feeling a little bit of slowing down of Internet traffic going to the United States," said Bill Barney, chief executive of Pacnet. He declined to name the damaged cables operated by other companies, but said Pacnet's cable system connecting Japan to the US had not been damaged.

While the extent of the damage to undersea cables is still unclear and financial losses unknown, operators said they are undergoing an inspection and looking to expedite restoration. Pacnet aimed to repair two damaged segments of its East Asia Crossing network connecting Japan to other parts of Asia, like Taiwan and Hong Kong within five to seven days, Barney said. He played down concerns about any financial impact on Pacnet or regional telecom operators from the damaged cables. "It's in our business plan that our cables will break, typically you get cuts in cables anywhere from five to 10 times a year," Barney said.

Several other companies also reported problems. The Japanese telecom operator KDDI said one of its undersea cables between Japan and the US had been damaged by the earthquake and was unable to transmit any signals. A spokesman said the company did not know if the cable was cut or having connection problems.

Identifying the problems may take some time as in some cases the damage is a long way off shore. KDDI said it was making efforts to identify and address the problem but added that services were beginning to recover after the quake.

Pacific Crossing, a unit of Japan's NTT Communications Corp. that operates a cable network between Japan and the US, also reported issues with its infrastructure. The Pacific Crossing PC-1 W and PC-1 N parts of its network remained out of service due to the earthquake, the company said.

NTT Communications said some of its services for enterprises were partially unavailable in Japan's Tohoku region, but that for submarine cables between Japan, other parts of Asia and the US the company was using backup cable routes. As regards its telephone services NTT say that it had restored  90% of its affected exchange offices some two weeks after the quake [Telegeography / NTT].

PCCW Ltd., which provides broadband Internet in Hong Kong, said Internet traffic to some international destinations, especially the US, were experiencing slower speeds due to several damaged cables that land in Japan, but it did not release details. In a statement PCCW said the affected cables would be repaired in "the coming weeks."

The Taiwan operator Chunghwa Telecom Co. was one of the first to acknowledge problems with connectivity following the earthquake. On the same day an official said the earthquake had caused damage to an undersea cable near Kita on the eastern coast of Japan that belongs to the Asia Pacific Cable Network 2, owned by a consortium of 14 telecom operators led by AT&T.

China Telecom Corp., China's largest fixed-line operator by subscribers, was making emergency repairs to undersea cables damaged by the earthquake, Xinhua News Agency reported. The company said submarine fiber-optic cables connecting Japan and North America and a Pacific Crossing 1 cable near the city of Kitaibaraki, in Japan's northern Ibaraki Prefecture, were malfunctioning due to the earthquake.

Xinhua, citing an official from China Telecom, said the company had restored 65 gigabytes of outbound capacity, after the earthquake had disrupted 105 gigabytes of outbound Internet capacity and another 7 gigabytes of privately leased cable capacity.

Meanwhile China Mobile Ltd., the world's largest mobile carrier by accounts, said most of the company's services were operating normally despite a surge in calls to Japan, Xinhua reported. Another telecom operator China Unicom Ltd. said most of its circuits had been repaired but cited connection problems with the network of Japan's NTT Communications.

Several companies said they avoided significant service disruptions by rerouting data traffic, including South Korean telecom operator KT Corp., which said a cable that is part of the Japan-US Cable Network was cut.

In the Philippines, Bayan Telecommunications Inc. said the earthquake had disrupted some of its digital subscriber line services but said they would normalize services within a day.

Some operators were apparently unaffected by the disaster which befell the region . A spokeswoman for Australian operator Telstra Corp. said none of the company's undersea cable infrastructure was damaged.

Rolling blackouts

In Japan itself the problems are further compounded by rolling electricity blackouts. Data centres have been hard hit with some being forced to shut down or run on expensive diesel generators for the time the power is off. If a data centre goes down this can be a major problem for websites hosted there. For anyone using search engine optimisation it can result in rankings being ditched by Google as it constantly crawls the web. If it finds a website offline for a period of time Google may delete the associated ranking. This poses a problem as it can take much time, effort and even money to bring those rankings back to where they were before. The Japanese economy has already been severely affected by the after effects of the earthquake and tsunami. Some industrial production has slowed or even halted and electronics markets are particularly concerned at present. For companies promoting themselves on the Internet, a downed website and extra costs is the last thing any impacted company needs [Seoconsult].

Previous Internet failures

It is not the first time that the Internet and telecommunications have been disrupted due to earthquakes. In December 2006 a massive 7.1 magnitude quake off the coast of Taiwan caused disruption to Asia's Internet [tvnewswatch - Dec 2006]. It took at least a month before the damage was repaired [tvnewswatch - Jan 2007]. In late 2008 millions were cut off after a cable was severed in the Mediterranean Sea [tvnewswatch - Dec 2008]. The cause of the failure in that case and another earlier in the year was not immediately identified [tvnewswatch - Jan 2008].

Most international Internet data and voice phone calls are transmitted as pulses of light via the hundreds of undersea fiber optic cables that crisscross the globe. The cables, which can cost hundreds of millions of dollars, are typically owned by consortia of telecom companies, who share costs and capacity. While the clusters of glass fibers are enclosed in protective material, they remain vulnerable to undersea earthquakes, fishing trawlers and ship anchors. There are also many choke points around the globe where a number of key cables converge.

As the number of people using the Internet grows there is an ongoing struggle to provide the much needed capacity. Demands for faster speeds has also increased the stress on an over-saturated network. When significant parts of that network fails it forces traffic to be rerouted, and while a connection may be maintained it may not be as reliable or as speedy as before. In China the Internet is continually being disrupted by government censors. The cutting of cables to the outside world has, for many, compounded the problem to the extreme.

tvnewswatch, Beijing, China

1 comment:

cable companies in my area said...
This comment has been removed by a blog administrator.