Optus told the committee it determined the cause of the outage was a number of key routers disconnecting themselves from the Optus network in response to a change in routing information.

At 4:05am eastern time, 90 Optus routers went down. Engineers were scrambling for a fix within half an hour. By 7:35am, Ms Bayer Rosmarin was on site at Optus' Sydney headquarters. At 8:30am ...