wow there is a lot of miss information in this thread, specially when its comes to the DSL network. Copper is the underlying issue with the DSL network through and through! This has nothing to do with the backbone of TLS or OPT or matter of any other carrier that supplies that..
Given the complaints of users vs bandwidth on DSL no carrier has a garunteed CBR to any consumer user so depending on the bandwidth (from DLSAM to agregator then into the cloud etc) of each exchange or POI so this point is then irrelevant. Keep in mind that also home networking will become an issue with multi person streaming but thats a whole nother kettle of fish
TLS whole network is fibre through out including to their mobile base stations
OPT has fibre backbone to its 13 super exchanges and has a lot of leased lines
i can go on all day here however given this is about the NBN which is a great idea for AUS given we are 10+ years behind the rest of the world carrier wise this will be good to bring us into the future of bandwidth and tele confrencing etc etc etc