Australia's biggest ISP has suffered two major blows to its network in as many days.

After a deep sea cable slash yesterday caused unprecedented delays for all Telstra customers attempting to log onto international Web sites, the ISP sustained a second outage Tuesday morning when a fire at Energy Australia's Paddington sub-station shut off power to most of Sydney's Eastern Suburbs.

A Telstra spokesperson said the ISP's Eastern Suburbs servers were back up and running, after the 650,000-customer ISP automatically sourced alternative power from its five Sydney-based diesel generators.

-Telstra has a lot of spare battery power," the spokesperson said.

The spokesperson said it was possible that the re-routed international traffic - due to the slashed cable - affected the ISP's ability to efficiently route traffic via its Eastern Suburbs server.

-It [the cut cable] has had a great effect on Bigpond," he said.

Bigpond is Telstra's ISP business.

Telstra said the cable that connected the ISP's Australian customers with Asia, Europe and the Middle East, SEAMEWE3, was cut at the bottom of the ocean near Singapore around midday yesterday.

The mishap partially cut off more than half a million Telstra customers from the rest of the world.

It was impossible to say what caused the cut or how soon it would be repaired.

The cable normally directs around 60 percent of Telstra's international Web traffic. Telstra was able to operate at around 75 percent normal capacity after it re-routed international traffic through alternative networks, officials said.

Energy Australia expected electricity to be returned to around half the 20,000 affected homes and businesses by late Tuesday.

Read more on Telstra's Cable Mishap

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