If using a third party router, make sure you enable bandwidth control (sometimes called traffic shaping) on your router so that you do not upload faster than the speed of your plan. If you upload more than the plans speed this can cause your connection to drop as NBN will start discarding information you send across the connection.
All TPG supplied routers do this automatically to ensure you have the fastest and most stable connection possible.
The guide for doing this on a Netgear modem is below.
To create a QoS policy.
Connect your computer to the Netgear modem and launch a web browser.