5G Mobile Broadband Working But Issues With Smart Devices.

Hello,

Bit of a strange one.

5G recently went live in my town, so I invested in a Huawei CPE Pro 2 and a Three pay monthly SIM (Not their home broadband specific one).

I received the 5G CPE Pro 2 and plugged it into my main router and put the CPE Pro 2 into bridge mode - all works fine, my router clocks the IP address. Better still, I can seem to open any port I like through the 3internet APN. Speeds are rapid, all is great.

Then I discover that my Philips Hue and Google Home Minis are no longer working, they seem to be having trouble communicating with the internet (LAN seems to work fine).

Does anyone know of any issues that might be causing this? I can't see it being CGNAT because i'm able to port forward on an IPv4.

Annoying still, when I switch my WAN back to my old Plusnet connection - all works fine.

I just wondered if anyone may know what the issue is? I'm hesitant to ring Three incase there is an awkward conversation as to why i'm using a standard Pay Monthly SIM instead of the pricier Mobile Broadband ones - but is there really any difference between the two?

Thanks in advance!

IIRC that is the .ie domain APN. Try APN three.co.uk which is what I have on my phone.

In reply to a post by pluralist:

IIRC that is the .ie domain APN. Try APN three.co.uk which is what I have on my phone.

A few years ago it was stated that "three.co.uk" is for phones which gives you a CGNAT IP and "3internet" was for hotspots / tablets and gave you a public IP. Given how scarce IPv4 is now this could change any day.


(The other networks only offer public IP for corporate / enterprise customers)

Edited by jchamier (Sun 27-Jun-21 12:41:27)

Remind me how you check for being on CGNAT please, as 3internet is what my router is on.

In reply to a post by pluralist:

Remind me how you check for being on CGNAT please, as 3internet is what my router is on.

Yes mine is on 3internet too. I check to see whether the router returns a public IPv4 - typically I find that if it is CGNAT it issues an IPv6 address only.

It also allows me to port forward my Synology NAS etc.

Edited by Nitro93 (Sun 27-Jun-21 17:48:26)

Visit a site such as ipchicken.com or ask google “what is my IP address” and compare that to the IP address reported by your router for the WAN connection.

If they are the same, you are unlikely to be behind CGNAT.

Thanks .

Laptop via router they are the same.
Laptop via phone different from each other.

In reply to a post by pluralist:

Laptop via router they are the same.

Great, a benefit of using Three in your router.

Laptop via phone different from each other.

As expected, and would be the same on other networks.

If you had an iPhone it is impossible to see the IP the mobile network allocates, you can for WiFi. But on Android it is easy.

Just thought i'd follow up with how I solved this incase others run into the same issue, turns out the 5G CPE Pro 2 defaults to 1500 MTU. I changed this down to 1300 and all is working properly!