Using external modem and Three 5G hub as a router only

[JusByf]

I am getting an external 5G modem (i.e. one that is mounted outside, to receive best signal) and want to connect it to the Three 5G hub for use as the router.  Is it as simple as plugging the Ethernet cable in to one of the LAN/WAN ports on the Hub, or are there other settings to change on the Hub in order to make it work?

The external modem is POE and can broadcast a wifi signal, but I intend to use the IP passthrough feature to disable that function and use the signal from the Three Hub to connect my devices, as I am doing currently.

I'd be most grateful for your thoughts.

JB

[JonathanB]

Hey @JusByf,

To my understanding if the Three router will be acting as Wi-Fi router, and it's the 3rd party external device that will be the modem, it's just the external device that would need set to IP passthrough or bridge mode. We don't supply our routers with this set up in mind though, so my info is limited.

I'm assuming the Three 5G SIM is going to be inserted in the external device?

Thanks,
Jonathan

[JusByf]

Hi Jonathan.  Thank you for your reply.  Yes, the Three SIM will be in the external modem.

I have found that there is a 'Cable Modem' mode on the Three Hub, accessed as an option alongside Bridge and Wifi router modes.  Selecting this appears to enable one of the LAN ports as a WAN port for the incoming connection from the external modem. 

Having read-up on IP passthrough, I understand that I will need to configure the modem to use the router's MAC address so the modem appears as the target for incoming wifi connection.  Does this sound right to you?

I'd be grateful for any other guidance you or others can offer.

I will post my findings when the router is set up.

[PeteG]

Hello. 

As Jonathan isn't around just now, I thought I'd take a bash at answering this. 

What you've described mostly sounds right, however the last part about needing to configure the modem to use the router MAC isn't something I'm aware of as a requirement. With the External device in Passthrough mode, you should be able to hook up the ethernet to the Three Hub, and DHCP should configure the device correctly. Then any devices you connect to the Hub Wifi should run normally after you connect them. 

I could be wrong though, as I'm not familiar with the External product you're using, but it's not a process I've ever had to follow my self when setting up a network. 

Pete.