NTT West has revealed that the failure of Internet communication using optical lines that occurred last week was caused by a failure of the transmission equipment that connects the network.
At the company, the backup equipment also failed at the same time, so it took a long time to recover, so we decided to take measures to prevent recurrence.
Due to the communication failure on the 25th of this month, it was difficult to connect to the Internet communication service using the optical line in a wide area such as Kansai, Tokai, Hokuriku, Chugoku and Kyushu for about 6 hours from 9 am.
On the 29th, the company revealed that as a result of the investigation, up to 2.11 million lines were affected by the communication failure, of which the maximum 630,000 lines were completely disconnected for 48 minutes.
Regarding the cause, it is said that the transmission equipment that connects the network broke down, and the spare equipment also broke down at the same time, so it took time to grasp the situation and restore it.
The company will further investigate the cause of the failure and take measures to prevent recurrence.
NTT West said, "We deeply apologize for the delay in notifying our customers that an unexpected event occurred and it took time to restore. We will review the design and promote prevention of recurrence." talking