Hackett also questioned the Coalition's claim that a minimum speed of 25Mbps will be good enough for most Australians.
"The demand for broadband [would have] to magically plateau on a permanent basis at two to three times the current demand we see in the market," he said.
The FTTN approach also could result in a "digital divide" even within a single community, with different populations getting different speeds on the network, Hackett said.
For example, new greenfield developments will be built with fibre to the premise and so could end up with many times the speed of older neighborhoods, he said.
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