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What is an NBN network and is my NETGEAR DSL modem router compatible? | Answer | NETGEAR Support
They seem to have updated this recently.
It says that users with Hybrid Fiber-Coaxial (HFC) have to use "a cable modem or gateway to connect them to the Internet".
In this case, you may have to connect the device to the WAN/Internet socket on the back of the D6400.
There are quite a few messages around here about NBN. The problem is that this service comes in different flavours. So what works with your D6400 might not work with someone else's.
