August 3, 2022 Administrative Guidance to KDDI Corporation and Okinawa Cellular Telephone Company Concerning Appropriate Response to Telecommunications Accident

Today, the Ministry of Internal Affairs and Communications (MIC) issued a stern warning to KDDI Corporation (headed by TAKAHASHI Makoto, President, Representative Director) and Okinawa Cellular Telephone Company (headed by SUGA Takashi, Representative Director and President) regarding a large-scale accident that occurred on July 2, 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 July 28, 2022, MIC received a serious accident report under Article 28 of the Telecommunications Business Act (Act No. 86 of 1984) from KDDI Corporation and Okinawa Cellular Telephone Company on the large-scale communication failure they experienced with their mobile phone services on July 2, 2022.
This accident was related to voice transmission services that handle emergency calls. In addition, the accident caused difficulty using voice transmission services (estimated to have affected approximately 23.16 million people with the two companies combined) and data transmission services (estimated to have affected approximately 7.75 million people with the two companies combined) for a duration of 61 hours and 25 minutes. Accordingly, the accident is found to have had an extremely significant social impact, given that mobile phone services are part of important infrastructure for people’s everyday lives. In particular, as the accident hindered use of services including emergency calls for about two and a half days, it had enormous effects on not only general users, but also on services in fields including physical distribution, transport, finance, and public services, as well as on mobile virtual network operators (MVNOs) to which the companies provide their lines.
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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