NTT Docomo submitted a report to the Ministry of Internal Affairs and Communications on the 16th, which summarizes the detailed causes and scope of impact of the two communication failures that occurred last month.

At NTT DoCoMo, communication failures occurred one after another on the 17th and 20th of last month, making it difficult for some users in western Japan to use the Internet service.



According to the outline of the report released by the Ministry of Internal Affairs and Communications, on the 17th, about 2.42 million people were affected for nearly five hours from 8:00 a.m. on the 20th, and about 690,000 people were affected for about two hours from 1:00 a.m. on the 20th. I think it has been affected.



As for the cause, the failure on the 17th was due to a failure of the communication equipment, and the function to detect the failure did not work properly, and the switch to the backup device was delayed, which prolonged the impact.



In addition, the failure on the 20th occurred during the construction of the Internet facility, and it is said that the error in the procedure manual itself was the cause of the communication failure.



The Ministry of Internal Affairs and Communications considers the two communication failures to be ``serious accidents'' as stipulated by the Telecommunications Business Law due to the extent of their impact and the time it takes to restore them. I am going to