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KDDI finally restores mobile service after 86-hour failure

Minister criticizes company for not providing information quickly

KDDI's service outage hit 39.15 million mobile connections and disrupted banking systems. (Photo by Yo Inoue)

TOKYO (Kyodo) -- KDDI Corp. said its "au" mobile phone service had been fully restored by Tuesday afternoon, ending 86 hours of service disruptions that affected millions of customers and a range of business activities.

But the company's woes were far from over amid mounting criticism of its handling of the unusually long network disruption, including from the regulator, while affected customers called for proper compensation.

The company said the previous day that voice calls and data communications had almost been restored nationwide after the disruption that commenced in the early hours of Saturday.

The service outage affected up to 39.15 million mobile connections, disrupting banking systems, the transmission of weather data, parcel deliveries and network-connected cars, among other things.

Earlier Tuesday, Internal Affairs and Communications Minister Yasushi Kaneko criticized KDDI for its handling of the disruption, saying the mobile operator failed to provide sufficient information to customers in a timely manner.

The company "has not fulfilled its responsibility as a telecommunications operator," with some customers still unable to make voice calls after KDDI said it had ended restoration work Sunday, Kaneko told reporters.

Taking into account the unprecedented impact of the outage, the government will set up an expert panel to compile measures to prevent a recurrence, Kaneko said.

Referring to the disruption of emergency calls, the minister said, "It is extremely regrettable that it has got to the point of potentially threatening people's lives and we are taking the situation seriously."

KDDI, Japan's second-largest mobile carrier by subscribers, first suffered a disruption at around 1:35 a.m. Saturday. The company said Monday afternoon that its services had almost been restored nationwide, but it stopped short of announcing the problems were resolved, saying it still needed time to check its network.

The company said Tuesday its services had fully been restored as of 3:36 p.m.

The Japan Meteorological Agency has demanded that KDDI come up with measures to prevent a similar incident after some data distribution from its regional weather observation system was suspended.

The system observes and distributes temperature and precipitation data. Of the around 1,300 observation stations nationwide, about 550 had stopped transmitting data due to the outage, Land, Infrastructure, Transport and Tourism Minister Tetsuo Saito said, adding the situation had returned to normal.

"Real-time observation data from the system is important for local people and organizations involved in disaster prevention," Saito told reporters Tuesday.

Health minister Shigeyuki Goto has requested the country's 47 prefectures to make efforts to prevent any impact on medical services in the event of a similar situation, he told reporters Tuesday.

Some municipalities had reported that medical facilities were unable to communicate with on-call doctors and drivers who were delivering pulse oximeters to coronavirus patients because of the outage, he said.

"To ensure there is no serious interference with medical and nursing-care services, we will work with prefectural governments to secure a stable system," Goto said.

The network failure occurred when a router for voice calls was replaced during regular maintenance, with repair work triggering a concentration of traffic that led the company to reduce user access.

During that time, the carrier experienced a cascade of technical problems that further prolonged the connection difficulties.

The latest service outage follows a system failure at NTT Docomo Inc., Japan's largest mobile carrier, in October last year that lasted around 29 hours and affected at least 12.9 million users.

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