The upgrades will improve the telco's HFC network in Melbourne, Sydney, Brisbane, Adelaide and Perth, and dwarf the government's proposed minimum 12Mpbs speeds for the National Broadband Network (NBN).

The speed of Telstra's Melbourne network will more than triple thanks to a rollout of the at a total upgrade cost of A$300 million (US$191.45 million).

Telstra CEO Sol Trujillo said the latest DOCSIS version has been successfully rolled out overseas.

"Late last year, Telstra foreshadowed that we would continue our investment in our cable network and, with the DOCSIS 3.0 software now well established internationally, we have the ability to dramatically increase speeds into Australian homes," Trujillo said in a statement.

"Now we are going to [have] super-fast broadband with download speeds among the highest in the world."