The main thing to check is whether your modem or router plugs into a telephone wall socket.
What to look for:
- A regular phone socket on the wall
- Your modem or router plugged straight into that socket
- No separate nbn connection box between the wall and your modem

In simple terms:
- If your internet comes from a phone wall socket
- And your modem or router plugs into that socket directly
- You may have FTTN or FTTB
As a general guide, FTTN is more common in houses, while FTTB is more common in apartments or units.
For BYO setup, both FTTN and FTTB normally need a VDSL-compatible modem/router.