In general, unless indicated differently by the MFD manufacturer (Navico/Garmin/Raymarine/Furuno), it is best to leave the manufacturer’s wired Ethernet network, just for connecting the manufacturer’s equipment together and if you want to provide the system with an internet connection, to do this by connecting the master MFD wirelessly to our 4GXtream.
This will result in having two wired Ethernet networks on the boat, one for the navigation equipment and the other for internet access and normal IT type networking, but it will result in the most reliable operation of the two networks.
Most MFD manufacturers do not want customers to open up their Ethernet network to either a conventional LAN or WAN environment that they have no control over. Unknown network devices, levels of network data and protocols, that the manufacturer has never tested against, could potentially have serious, negative effects on the operation of their equipment.
The MFD’s wireless interface will be on a separate subnet and “locked down” so that it just does what they need it to do and no more. When you tell the wireless interface to join another wireless network in STATION (STA) mode, rather than its default ACCESS POINT (AP) mode, it will get an IP Address for the wireless interface from the 4GXtream and be able to go online for updates, weather data, etc.