In Japan, Many Undersea Cables Are Damaged

The horrific earthquake and the ensuing tsunami in Japan have caused widespread damage to undersea communications, according to data collected by telecom industry sources. Initially, it was thought that the damage to the cables that connect Japan and Asia to each other and other parts of the world was limited, but new data shows the extent of the problems.

According to research firm, Telegeography, the following cables have been damaged:

  • APCN-2, which is an intra-Asian cable, forms a ring linking China, Hong Kong, Japan, the Republic of Korea, Malaysia, the Philippines, Singapore and Taiwan.
  • Pacific Crossing West and Pacific Crossing North, which are out of service.
  • PacNet has reported outages on segments of its East Asia Crossing network.
  • Korea Telecom reports that a segment of the Japan-U.S. Cable Network is damaged
  • NTT has reported damage to some segments of the PC-1 submarine cable system.

Most of the damaged network routers land in the Ajigaura or Kitabaraki landing stations, which are between Tokyo and Sendai (see map.) The tsunami and earthquake have not damaged Japan’s cable landing stations that are in the South of Tokyo, or on other side of the sheltered inlet that becomes Tokyo Bay, Telegeography said.

“We’re not aware of disruptions to any of the many cables that land here,” Stephan Beckart of Telegeography wrote in an email. “All of the cable systems that have reported outages also operate cables that land to the South of Tokyo, so no system appears to have suffered a complete outage.

A report from Dow Jones Newswires suggests most companies are working hard to fix the network problems. The Dow Jones report has the following additional details:

  • KDDI says its cable between the U.S. and Japan is broken and it cannot transmit signals.
  • NTT is using back-up cable systems.
  • PCCW says the Internet traffic to the U.S. is slow.

In a story on Friday, Stacey Higginbotham pointed out that Chunghwa of Taiwan had reported an outage on the APCN-2 system, while China Unicom had reported some unspecified damage to “two or three cables.” There is clear decline in Japan’s Internet performance, according to the data from JPNAP.