September 30, 2022 Administrative Guidance to Nippon Telegraph and Telephone West Corporation (NTT West) Concerning Appropriate Response to Telecommunications Accident

Today, the Ministry of Internal Affairs and Communications (MIC) issued a stern warning to Nippon Telegraph and Telephone West Corporation (headed by MORIBAYASHI Masaaki, President, Executive Director) regarding a large-scale accident that occurred on August 25, 2022, so as to prevent recurrence of similar accidents. In addition, MIC gave them administrative guidance in writing, instructing them to securely implement various initiatives from the viewpoint of recurrence prevention.

1. Background

On August 25, 2022, MIC received a serious accident report under Article 28 of the Telecommunications Business Act (Act No. 86 of 1984) from Nippon Telegraph and Telephone West Corporation on the large-scale communication failure they experienced with their Internet communication services on September 26, 2022.
This accident caused difficulty using the Internet communication services (estimated to have affected approximately 2.11 million people) for a duration of 5 hours and 47 minutes. Accordingly, the accident is found to have had an extremely significant social impact, given that the Internet communication services are part of important infrastructure for people’s everyday lives.
Such a serious accident is a major disruption to users’ interests and seriously affects social and economic activities. Therefore, MIC issued a stern warning to the companies to prevent similar accidents from occurring and gave them administrative guidance in writing from the viewpoint of recurrence prevention.

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