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April 19, 2012


Lessons Learned from the Tohoku Earthquake

April 19, 2012

Yesterday, NCTA hosted an event at our offices to help educate about the impact of the March 2011 earthquake on the telecommunications infrastructure of Japan. Representatives from the Japanese Embassy here in Washington and executives from NTT East, a leading Japanese telecom provider, described the damage of both the quake and the ensuing damage of the massive tsunami that followed, efforts to repair and replace equipment and facilities and the lessons they learned that can be used to prepare for future incidents.

The Tohoku earthquake that struck on the afternoon of Friday, March 11, was the largest seismic event in Japan’s recorded history, with a magnitude of 9.0. A half hour later, the east coast of Japan was hit by a tsunami which reached 50 feet in height, and covered 400 miles of coastline — roughly the distance between the District of Columbia and Boston.

NTT East lost 65,000 poles, 1,900 miles of conduits and 5,000 miles of cables. Some central offices were destroyed or flooded. Massive power outages strained the resources of their backup equipment.

At the same time, their network was hit with an enormous jump in activity, with outgoing voice traffic jumping 60-fold in the hours after the quake, and incoming calls increasing 40-fold.

Carriers had to restrict fixed phone line voice traffic by 80-90%, and mobile phone traffic by 70-95%. Packet traffic also increased, but only by about four times as much as the previous week. In addition to congestion from voice calls, emails were delayed as well. Just 15 percent of email was delivered immediately, 80% went through within 30 minutes and 90% was delivered within 80 minutes.

NTT East set up 4,000 free public phone lines in evacuation centers and hospitals, and provided broadband access to 450 locations. It also deployed 100 power supply vehicles as a fail-safe in case backup generators died, and dispatched remote terminals to replace demolished central offices. In order to allow families to connect with loved ones in the face of staggering congestion, NTT East already had in place a “171” voice message system. People could call in and leave a message. Family members could call in to the system and retrieve those messages by punching in the cell phone number. NTT East workers who found handwritten notes at rescue stations would manually enter those messages into the 171 system. Unfortunately, because the different mobile carriers systems weren’t interoperable, you would need to know what carrier your target was using in order to get their message; since the quake, the carriers have been working on making the systems interoperable.

NTT has negotiated with convenience store chains to pre-install Wi-Fi lines and emergency public phones, which can be turned on during emergencies and used free of charge. NTT also has introduced vehicles with mobile Wi-Fi stations and special antennas that can reach more than 10 miles.

Other recommendations from a study group include: developing new technology that’s resistant to congestion, introducing more emergency power sources, and encouraging roaming agreements between telecom carriers for emergency calls.

Also present were representatives from various governmental agencies. From such tragedies, hopefully we can all learn how to prepare for the future.