"At that time, connecting" Softbank disaster countermeasures that continue to evolve for 10 years since the Great East Japan Earthquake

At 2:46 pm on March 11, 2011, a huge earthquake with a seismic intensity of 7 off the coast of Sanriku and an unprecedented tsunami caused a huge damage caused many lives.10 years since then.Softbank is working in preparation for various disasters based on the lessons learned from the Great East Japan Earthquake.Looking back on the 10 years of initiatives.

Efforts for disaster countermeasures are accelerated based on the lesson of the Great East Japan Earthquake

When the Great East Japan Earthquake occurred, Kazuhiro Kobayashi, who was a member of the Mobile Network Headquarters Tohoku Technology Department (Sendai City, Miyagi Prefecture), said, "The nationwide employees helped each other and worked together as a company.I think that it was an unprecedented experience that many people had moved in the direction, and I would like to continue to combine the power of employees and make use of the earthquake. "

With the shaking and the tsunami of the Great East Japan Earthquake, 3,786 stations at the mobile communication base station were out of connection, and fixed communications affected the line about 178,000, and the communication network in the affected areas was catastrophic.Immediately after the earthquake, the SoftBank was set up by the Disaster Countermeasures Headquarters, and employees from all over the country to recover the line as soon as possible.Eventually, 789 technical employees and 440 volunteers gathered to respond.

About one month after the earthquake, on April 14, 2011, about 95 % of fixed communications and mobile communications were restored to the same level as before the earthquake.More than six months later, on September 30, 99%of fixed communications finally recovered.

With the idea that "we will regain the connection as soon as possible, as soon as possible," SoftBank's efforts on disaster countermeasures accelerated at once.

Construction of a disaster -resistant network

As a premise of recovering communication quickly, the communication network must be highly durable for disasters.The network center, the center of the communication network, has been reviewed in a design that can withstand the seismic intensity of the building after the Great East Japan Earthquake.In addition, major network centers around the country have no power outage devices (batteries) and emergency generators, and power outage measures are being implemented to operate up to 72 hours from 48 hours to 72 hours when commercial power is lost.

And the network nationwide has a mutual backup in the East Japan area and the West Japan area, and the transmission network is also built in a ring, so even if there is a equipment failure in one place, detour connection is possible.Countermeasures such as doing are being applied.

In the Great East Japan Earthquake, power outages occurred in a wide area.If the power supply to the base station stops, communication will be interrupted.As a countermeasure against blackouts, a power supply equipment that can be maintained for more than 24 hours for base station equipment has been installed.Recently, the introduction of generators that can supply power for more than 72 hours has begun.

"We have installed generators and batteries to prevent the operation of base stations and take power countermeasures. In parallel, a satellite antenna is set up as a measure against the optical optical cable that is drawn into the base station.We are preparing to maintain communication "(Area Restoration Headquarters Yasunori Toyohara)

At that time, many base stations were played by the tsunami, so mobile base stations, mobile power supply vehicles, and portable base stations played an important role in order to quickly restore communication areas.Based on that, the deployment of mobile base stations was increased to 100 units and 82 mobile power vehicles.There are 200 new cars nationwide.In addition, on March 11, 2016, the "Mailball Balloon Radio Relay System" can be used on the commercial network due to the revision of the legal system for the Radio Law Remarks.This system had been researched and developed as a method of temporarily recovering the communication area using mooring balloon when a network on the ground was disaster.It was deployed at major bases.