Your biggest challenge is likely to be access to dark fibre or leased-lines at acceptable prices that allow you to make money. Licensed wireless backhaul is often the way to go, but that gets expensive quickly and also some existing spectrum there is likely to get re-allocated to 5G.
There are already plenty in Aus: Clear Networks (VIC - Melbourne & many regional) BigAir (NSW) Uniti (VIC - Melbourne, SA - Adelaide) The Signal co (ACT - Canberra) Netspeed (ACT - Canberra) nuSkope (SA - Adelaide, QLD - Brisbane) Red Broadband (WA - Perth) Node 1 (WA - Perth & Geraldton) AirFiber (NSW - West Sydney)
And others.
Good discussions on http://forums.whirlpool.net.au/forum/18
Your biggest challenge is likely to be access to dark fibre or leased-lines at acceptable prices that allow you to make money. Licensed wireless backhaul is often the way to go, but that gets expensive quickly and also some existing spectrum there is likely to get re-allocated to 5G.