At about 01:30 this morning my connection failed. I went to bed and checked it again in the morning. It was still down. When I rang Netspace (my new ISP), there was a recorded message saying that all Netspace customers might be experiencing "authentication" difficulties. Certainly my modem was not authenticating ... the network appeared to be unreachable.
This message stayed on the tech support line most of the day. At about 15:00, I rang customer service. They told me their had been an outage, and that it was a Telstra issue, and that the issue was now resolved. My domain was still down however. It seemed that the auto-restart script I had left running on the firewall was not re-connecting. I reasoned that a "reboot" was not severe enough. So I cycled the power on the modem when I returned at 17:30. Still not good enough I turned off the power and left it for three minutes. Finally I turned off the power, shutdown the firewall and then let it re-negotiate with the modem. Then, after restarting the firewall scripts and rebooting the modem twice ... Finally, the connection was re-established.
Nasty things these Telstra outages. Hope we don't see too many of them.