Nextgen Networks is suffering a cut fibre on one of their paths between Sydney and Melbourne.
The fibre network operator's managing director Phil Sykes told iTnews that maintenance and splicing crews were dealing with the outage.
He said traffic had been redirected onto the firm's second discrete path between the capital cities.
"All of our protected services would not have even known there was a cut," Sykes said, adding the redirect occured automatically within 50 milliseconds.
Web hosting firm AussieHQ was the first to report the issue.
The company's service status said there was a cut "near Sydney" that had "caused the loss of connectivity between Canberra and Sydney.
"We are currently routing around the fault however customers may notice degraded performance at this time," the notification read.
An AussieHQ representative Shaun Ewing also posted in the Whirlpool internet forums, saying it sounded "pretty crazy in the background when calling the Nextgen network operations centre."
There were conflicting reports on which providers were affected by the cut.
Ewing said AussieHQ's "two primary upstream providers Internode and Vocus seem to be affected."
But Vocus chief James Spenceley - checking with his firm's own NOC (network operations centre) - said there were no network issues at his end.
He said in any event Vocus' path between Sydney and Canberra was protected because it could route via Melbourne.
More to come...