A common misconception is that the traditional cable broadband networks operated by Telstra and Optus are the same as Australia’s new National Broadband Network (NBN) that is currently being rolled out. This is only partly true.
Where the NBN relies on a fibre to the home (FTTH), a fibre-optic connection running all the way from its source to the premises, traditional cable uses fibre-optics only until they reach the node. The node is similar to the DSLAM in an ADSL network in that it is responsible for splitting and amalgamating the broadband signal between the ISP and its many users. From the node, the signal is transferred to coaxial copper wiring that takes it the last mile to premises.
Fibre-optic cable offers far superior speeds to the copper-based coaxial cabling, but is much more expensive to deploy. As such traditional cable broadband connections are essentially throttled once they reach the node and begin their final journey to the premises. http://www.whistleout.com.au/Bro ... -You-Get-it-and-Why